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CHRYSLER CORPORATION SERVICE MANUAL 1995 JEEP To order the special service tools used and illustrated, please refer to the instructions on inside back cover.

NO PART OF THIS PUBLICATION MAY BE REPRODUCED, STORED IN A RETRIEVAL SYSTEM, OR TRANSMITTED, IN ANY FORM OR BY ANY MEANS, ELECTRONIC, MECHANICAL, PHOTOCOPYING, RECORDING, OR OTHERWISE, WITHOUT THE PRIOR WRITTEN PERMISSION OF CHRYSLER CORPORATION.

Chrysler Corporation reserves the right to make changes in design or to make additions to or improvements in its products without imposing any obligations upon itself to install them on its products previously manufactured.

Litho in U.S.A. Copyright © 1994 Chrysler Corporation 20M0694

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FOREWORD

The information contained in this service manual has been prepared for the professional automotive technician involved in daily repair operations. This manual does not cover theory of operation, which is addressed in service training material. Information describing the operation and use of standard and optional equipment is included in the Owner’s Manual provided with the vehicle. Information in this manual is divided into groups. These groups contain general information, diagnosis, testing, adjustments, removal, installation, disassembly, and assembly procedures for the components. To assist in locating a group title page, use the Group Tab Locator on the following page. The solid bar after the group title is aligned to a solid tab on the first page of each group. The first page of the group has a contents section that lists major topics within the group. If you are not sure which Group contains the information you need, look up the Component/System in the alphabetical index located in the rear of this manual. A Service Manual Comment form is included at the rear of this manual. Use the form to provide Chrysler Corporation with your comments and suggestions. Tightening torques are provided as a specific value throughout this manual. This value represents the midpoint of the acceptable engineering torque range for a given fastener application. These torque values are intended for use in service assembly and installation procedures using the correct OEM fasteners. When replacing fasteners, always use the same type (part number) fastener as removed. Chrysler Corporation reserves the right to change testing procedures, specifications, diagnosis, repair methods, or vehicle wiring at any time without prior notice or incurring obligation.

NOTE: The acronyms, terminology and nomenclature used to identify emissions related components in this manual may have changed from prior publications. These new terms are in compliance with S.A.E. recommended practice J1930.

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GROUP TAB LOCATOR Introduction

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Lubrication and Maintenance

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Front Suspension and Axle

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Rear Suspension and Axles

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Brakes

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Clutch

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Cooling System

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Electrical

9

Engines

11

Exhaust System and Intake Manifold

13

Frame and Bumpers

14

Fuel System

16

Propeller Shafts

19

Steering

21

Transmission and Transfer Cases

22

Wheels and Tires

23

Body Components

24

Heating and Air Conditioning

25

Emission Control Systems Index

Service Manual Comment Forms

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INTRODUCTION CONTENTS page

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DESIGNATIONS, LABELS/PLATES, CODES AND DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . 1

MEASUREMENT AND TORQUE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . 11

DESIGNATIONS, LABELS/PLATES, CODES AND DIMENSIONS INDEX page Engine and Transmission/Transfer Case Identification . . . . . . . . . . . . . . . . . . . . . . . . . . International Vehicle Control and Display Symbols Major Component Identification . . . . . . . . . . . . . . Trailer Towing Specifications . . . . . . . . . . . . . . . . Vehicle Code Plate . . . . . . . . . . . . . . . . . . . . . . .

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VEHICLE DESIGNATIONS The Vehicle Code Designations chart lists the vehicle description and code for Cherokee and Wrangler vehicles. The codes are used to identify vehicle types in charts, captions and in service procedures. The vehicle codes are different than the Vehicle Identification Number (VIN) or the wheelbase/model code. The following illustrations shows the labels, decals and plates as well as locations on each vehicle.

page Vehicle Vehicle Vehicle Vehicle Vehicle

Designations . . . . . . . . . . . . . . . Dimension Data . . . . . . . . . . . . Identification Number (VIN) Plate Load Data . . . . . . . . . . . . . . . . Safety Certification Label . . . . . .

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INTRODUCTION

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VEHICLE SAFETY CERTIFICATION LABEL A vehicle safety certification label (Fig. 1) is attached to every Jeep vehicle. The label certifies that the vehicle conforms to all applicable Federal Motor Vehicle Safety Standards. The label also lists: • Gross vehicle weight rating (GVWR) and the gross front and rear axle weight ratings (GAWR’s) based on a minimum tire rim size and a maximum cold tire inflation pressure. • Month and year of vehicle manufacture. • Vehicle identification number (VIN). • Type of vehicle. • Month, day and hour (MDH) of final assembly. The label is located on the driver-side door shutface.

located on the lower windshield fence near the left A-pillar. The VIN contains 17 characters that provide data concerning the vehicle. Refer to the VIN decoding chart to determine the identification of a vehicle. The Vehicle Identification Number is also imprinted on the: • Body Code Plate. • Vehicle Safety Certification Label. • Frame rail. To protect the consumer from theft and possible fraud the manufacturer is required to include a Check Digit at the ninth position of the Vehicle Identification Number. The check digit is used by the manufacturer and government agencies to verify the authenticity of the vehicle and official documentation. The formula to use the check digit is not released to the general public.

VEHICLE CODE PLATE

Fig. 1 Vehicle Safety Certification Label—Typical

A metal vehicle code plate is attached to the left (driver) side of the dash panel in the engine compartment (Fig. 2). There can be a maximum of seven rows of vehicle information imprinted on the plate. The information should be read from left to right, starting with line 1 at the bottom of the plate up through line 7 (as applicable) at the top of the code plate. Refer to the decoding chart to decode lines 1 up through 3. Lines 4 through 7 (if used) on the vehicle code plate are imprinted on the plate (in sequence) according to the following:

VEHICLE IDENTIFICATION NUMBER (VIN) PLATE The Vehicle Identification Number (VIN) plate is

VEHICLE IDENTIFICATION NUMBER (VIN) DECODING


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5

The last code imprinted on a vehicle code plate will be followed by the imprinted word END. When two vehicle code plates are required, the last available spaces on the first plate will be imprinted with the letters CTD (for continued). When a second vehicle code plate is necessary, the first four spaces on each row will not be used because of the plate overlap.

ENGINE AND TRANSMISSION/TRANSFER CASE IDENTIFICATION When required, refer to Group 9, Engines for all engine identification data. Refer to Group 21, Transmissions for all transmission/transfer case identification data.

Fig. 2 Vehicle Code Plate VEHICLE CODE DECODING

MAJOR COMPONENT IDENTIFICATION When required, refer to the applicable service information group for major component identification data.

VEHICLE DIMENSION DATA The vehicle dimension data charts list the exterior and interior dimensions for each type of Jeep vehicle.

VEHICLE LOAD DATA The Vehicle Load Data chart lists the following information: • Gross vehicle weight rating (GVWR). • Gross axle weight ratings (GAWR). • Cargo weight. • Passenger weight for each Jeep type/body style.

TRAILER TOWING SPECIFICATIONS

• 3-character sales code. • 3-digit numerical code. • 6-digit SEC code. If there is not enough space left in the row for all of the 6-digit SEC code (if used): • The unused space will remain blank. • The code will be listed in the next row. The last nine positions of row 7 will contain a 2-digit code, when applicable, and a 6-digit gateline serial number (same as the last 6 numbers of the VIN).

The Trailer Towing Specification chart provide: • Minimum Vehicle requirements. • The maximum trailer tongue weight. • The maximum trailer weight. • The maximum combined weight of the trailer/load/ towing vehicle with a specific engine/transmission/ axle combination.

INTERNATIONAL VEHICLE CONTROL AND DISPLAY SYMBOLS Most of the graphic symbols illustrated in the following chart are used to identify various instrument controls and displays.


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VEHICLE DIMENSION DATA


INTRODUCTION

J VEHICLE LOAD DATA—XJ

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J VEHICLE LOAD DATA—YJ


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J TRAILER TOWING SPECIFICATIONS

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J VEHICLE CONTROL AND DISPLAY SYMBOLS


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MEASUREMENT AND TORQUE SPECIFICATIONS INDEX page

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Metric and English/Sae Conversion . . . . . . . . . . . . 11 Specification Notations . . . . . . . . . . . . . . . . . . . . . 11

Torque Specifications

SPECIFICATION NOTATIONS

It is important to be aware that the torque values listed in the chart are based on clean and dry bolt threads. Reduce the torque value by 10 percent when the bolt threads are lubricated and by 20 percent if new.

WARNING: THE USE OF INCORRECT ATTACHING HARDWARE CAN RESULT IN COMPONENT DAMAGE AND/OR PERSONAL INJURY. It is important to retain the original attaching hardware for assembly of the components. If the attaching hardware is not reusable, hardware with equivalent specifications must be used.

METRIC AND ENGLISH/SAE CONVERSION The following chart will assist in converting metric units to equivalent English and SAE units, or vise versa.

TORQUE SPECIFICATIONS TORQUE CHARTS A torque chart for fasteners is provided at the end of each group (of service information). Refer to the Torque Specifications chart to determine torque values not listed in the group.

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BOLT THREAD AND GRADE/CLASS IDENTIFICATION THREAD IDENTIFICATION SAE and metric bolt/nut threads are not the same. The difference is described in the Thread Notation chart. GRADE/CLASS IDENTIFICATION The SAE bolt strength grades range from grade 2 to grade 8. The higher the grade number, the greater the bolt strength. Identification is determined by the line marks on the top of each bolt head. The actual bolt strength grade corresponds to the number of line marks plus 2. The most commonly used metric bolt strength classes are 9.8 and 12.9. The metric strength class identification number is imprinted on the head of the bolt. The higher the class number,

CONVERSION FORMULAS AND EQUIVALENT VALUES


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J TORQUE SPECIFICATIONS


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J THREAD NOTATION—SAE AND METRIC

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imprinted with a single-digit strength class on the nut face. Refer to the bolt identification and bolt strength chart.

METRIC CONVERSION Refer to the chart to convert torque values listed in metric Newton-meters (Nzm). Also, use the chart to convert between millimeters (mm) and inches (in.)

the greater the bolt strength. Some metric nuts are


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J BOLT STRENGTH

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J METRIC CONVERSION


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LUBRICATION AND MAINTENANCE CONTENTS page

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CHASSIS AND BODY COMPONENTS . . . . . . . . 28 DRIVETRAIN . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 ENGINE MAINTENANCE . . . . . . . . . . . . . . . . . . . 15

GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1 JUMP STARTING, TOWING AND HOISTING . . . . 9 MAINTENANCE SCHEDULES . . . . . . . . . . . . . . . . 4

GENERAL INFORMATION INDEX page Classification of Lubricants . . . . . . . . Components Requiring No Lubrication Fluid Capacities . . . . . . . . . . . . . . . . Fuel Requirements . . . . . . . . . . . . . .

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page International Symbols . . . . . . . . . . . . . . . . . . . . . . . 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Lubrication and Replacement Parts Recommendation . . . . . . . . . . . . . . . . . . . . . . . . . 2

INTRODUCTION Lubrication and maintenance is divided into required and recommended service tasks. The required service tasks must be completed to verify the emission controls function correctly. The recommended service tasks should be completed to maintain safety and durability. This information will assist the service personnel in providing maximum protection for each owner’s vehicle. Conditions can vary with individual driving habits. It is necessary to schedule maintenance as a time interval as well as a distance interval. It is the owner’s responsibility to determine the applicable driving condition. Also to have the vehicle serviced according to the maintenance schedule, and to pay for the necessary parts and labor. Additional maintenance and lubrication information is listed in the Owner’s Manual.

INTERNATIONAL SYMBOLS Chrysler Corporation uses international symbols to identify engine compartment lubricant and fluid inspection and fill locations (Fig. 1).

FUEL REQUIREMENTS All gasoline engines require the use of unleaded gasoline to reduce the potentially harmful effects of lead to the environment. Also unleaded fuel is necessary to prevent damage to the catalytic converter/O2

Fig. 1 International Symbols sensor. The fuel must have a minimum octane rating of 87 based on the (R + M)/2 calculation method. CAUTION: UNLEADED FUEL ONLY must be used in vehicles equipped with a catalyst emission control system. All vehicles have reminders printed on the instrument panel below the fuel gauge and on the fuel filler door. The vehicles also have fuel filler tubes that are specially designed to accept only the small-diameter dispensing nozzles. It is illegal to bypass the design of an unleaded fuel filler tube and contaminate the fuel system.


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LUBRICATION AND MAINTENANCE

CLASSIFICATION OF LUBRICANTS Lubricating fluids and chassis lubricants are classified according to standards recommended by the: • Society of Automotive Engineers (SAE) • American Petroleum Institute (API) • National Lubricating Grease Institute (NLGI)

ENGINE OIL API CERTIFICATION MARK For maximum engine protection during all driving conditions, install an engine oil that contains the API Certification Mark (Fig. 2). The API Certification Mark indicates that the oil is certified to meet the most critical requirements established by the manufacturer. Conformance to API specifications is determined by tests that measure the ability of an oil to control: • Engine wear. • Bearing corrosion. • Sludge. • Varnish. • Oil thickening. • Rust. • Piston deposits.

J GEAR LUBRICANTS A dual grade is also used to specify the viscosity of multi-purpose gear lubricants. The API grade designation identifies gear lubricants in terms of recommended usage. CHASSIS COMPONENT AND WHEEL BEARING LUBRICANTS The chassis and wheel bearing lubricants that are recommended are identified by the NLGI Certification Symbol. The symbol contains a coded designation. This identifies the usage and quality of the lubricant. The letter G within the symbol designates wheel bearing lubricant. The letter L designates chassis lubricant. When the letters are combined, the lubricant can be used for dual applications. Use only lubricants that display the NLGI Certification Symbol (Fig. 3).

Fig. 3 NLGI Lubricant Container Certification/ Identification Symbol

LUBRICATION AND REPLACEMENT PARTS RECOMMENDATION

Fig. 2 The API Engine Oil Certification Mark SAE VISCOSITY GRADE An SAE viscosity grade is used to specify the viscosity of engine oil. SAE 30 specifies a single viscosity engine oil. Engine oils also have multiple viscosities. These are specified with a dual SAE viscosity grade which indicates the cold-to-hot temperature viscosity range. API SERVICE GRADE CERTIFIED The API Service Grade specifies the type of performance the engine oil is intended to provide. The API Service Grade specifications also apply to energy conserving engine oils. Use an engine oil that is API Service Grade Certified or an oil that conforms to the API Service Grade SH or SH/CD. MOPAR provides engine oils that conform to all of these service grades.

Jeep vehicles are engineered to provide many years of dependable operation. However, lubrication service and maintenance are required for each vehicle. When necessary, MOPARt brand lubricants and genuine replacement parts are highly recommended. Each MOPAR brand lubricant and replacement part is designed and to provide dependability and long service life.

COMPONENTS REQUIRING NO LUBRICATION There are many components that should not be lubricated. The components that should not be lubricated are: • Air pumps. • Generator bearings. • Distributors. • Drive belts. • Drive belt idler pulleys. • Rubber bushings. • Starter motor bearings. • Suspension strut bearings. • Throttle control cables. • Throttle linkage ball joints. • Water pump bearings.


J FLUID CAPACITIES Fuel Tank XJ .....................................................76.4 L (20.2 gal.) YJ(Standard) ......................................56.8 L (15 gal.) YJ(Optional) .......................................75.7 L (20 gal.) Engine Oil 2.5L ......................................................3.8 L (4.0 qts.) 4.0L ......................................................5.7 L (6.0 qts.) Cooling System 2.5L(XJ).............................................9.5 L* (10 qts.*) 2.5L(YJ) ........................................8.5 L** (9.0 qts.**) 4.0L(XJ) ........................................11.4 L* (12.0 qts.*) 4.0L(YJ) ......................................9.9 L** (10.5 qts.**) * Includes (2.2 L) (2.3 qts) for coolant recovery reservoir. ** Includes (0.9 L) (1.0 qt.) for coolant recovery reservoir. Automatic Transmission Dry fill capacity.* AW4 (XJ-4.0L)...................................8.0 L (16.9 pts.) 30RH (YJ-2.5L) .................................8.2 L (17.5 pts.) 32RH (YJ-4.0L) .................................8.2 L (17.5 pts.) *Depending on type and size of internal cooler, length and inside diameter of cooler lines, or use of

LUBRICATION AND MAINTENANCE

0-3

an auxiliary cooler, these figures may vary. Refer to Group 21, Transmission for proper fluid fill procedure. Manual Transmission AX4/5 (4X2) .........................................3.3 L (3.5 qts.) AX5 (4X4) ............................................3.2 L (3.3 qts.) AX15 (4X2) ..........................................3.1 L (3.2 qts.) AX15 (4X4) ......................................3.15 L (3.32 qts.) Fill to bottom of fill hole. Transfer Case SELEC-TRAC 242(XJ) .......................1.4 L (3.0 pts.) COMMAND-TRAC 231(XJ) ...............1.0 L (2.2 pts.) COMMAND-TRAC 231(YJ-Man Trans) ..1.5 L (3.25 pts.) COMMAND-TRAC 231(YJ-Auto Trans)....1.0 L (2.2 pts.) Front Axle MODEL 30 (YJ)..............................1.65 L (3.76 pts.) MODEL 30 (XJ)..............................1.48 L (3.13 pts.) Rear Axle MODEL 35 (XJ-YJ) ........................1.6 L (3.38 pts.*) 8-1/4 (XJ) .........................................2.08 L (4.4 pts.*) * When equipped with TRAC-LOK, include 2 ounces of Friction Modifier Additive.


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LUBRICATION AND MAINTENANCE

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MAINTENANCE SCHEDULES INTRODUCTION There are two maintenance schedules that show proper service intervals for Jeep Cherokee and Jeep Wrangler vehicles. Use the schedule that best describes the conditions the vehicle is operated under. When mileage and time is listed, follow the interval that occurs first. Schedule—A lists all the scheduled maintenance to be performed under normal operating conditions. Schedule—B is a schedule for vehicles that are usually operated under one or more of the following conditions. • Frequent short trip driving less than 5 miles (8 km). • Frequent driving in dusty conditions. • Trailer towing or heavy load hauling. • Frequent long periods of engine idling. • Sustained high speed operation. • Desert operation. • Frequent starting and stopping. • Cold climate operation. • Off road driving. • Commercial service. • Snow plow operation. • More than half of vehicle operation occurs in heavy city traffic during hot weather (above 90° F).

AT EACH STOP FOR GASOLINE • Check engine oil level and add as required. • Check windshield washer solvent and add as required. ONCE A MONTH • Check tire pressure and look for unusual tire wear or damage. • Check fluid levels of coolant reservoir, brake master cylinder, power steering and transmission. Add fluid as required. • Check all lights and other electrical items for correct operation. • Inspect battery and clean and tighten terminals as required. • Check rubber seals on each side of the radiator for proper fit. AT EACH OIL CHANGE • Inspect exhaust system. • Inspect brake hoses. • Rotate the tires at each oil change interval shown on Schedule—A: (7,500 Miles) or every other interval shown on Schedule—B: (6,000 Miles). • Check engine coolant level, hoses, and clamps. • Lubricate 4x4 steering linkage. • Lubricate propeller shaft universal joints and slip spline, if equipped.

After completion of off-road (4WD) operation, the underside of the vehicle should be thoroughly inspected. Examine threaded fasteners for looseness. HARSH SURFACE ENVIRONMENTS After vehicle operation in a harsh surface environment, the following components should be inspected and cleaned as soon as possible: • Brake drums. • Brake linings. • Front wheel bearings (2WD vehicles only). • Axle coupling joints. This will prevent wear and/or unpredictable brake action.

EMISSION CONTROL SYSTEM MAINTENANCE The schedule emission maintenance listed in bold type on the following schedules, must be done at the mileage specified to assure the continued proper functioning of the emission control system. These, and all other maintenance services included in this manual, should be done to provide the best vehicle performance and reliability. More frequent maintenance may be needed for vehicles in severe operating conditions such as dusty areas and very short trip driving.

SCHEDULE—A 7,500 MILES (12 000 KM) OR AT 6 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). 15,000 MILES (24 000 KM) OR AT 12 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage. 22,500 MILES (36 000 KM) OR AT 18 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Inspect brake linings. 30,000 MILES (48 000 KM) OR AT 24 MONTHS • Replace air cleaner element. • Replace spark plugs. • Adjust belt tension on non-automatic tensioning drive belts. • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage. • Drain and refill automatic transmission. • Drain and refill transfer case.


J 37,500 MILES (60 000 KM) OR AT 30 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Drain and refill manual transmission. 45,000 MILES (72 500 KM) OR AT 36 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage. • Inspect brake linings. • Flush and replace engine coolant, regardless of mileage. 52,500 MILES (84 500 KM) OR AT 42 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Flush and replace engine coolant if not done at 36 months. 60,000 MILES (96 500 KM) OR AT 48 MONTHS • Replace air cleaner element. • Replace distributor cap and rotor. • Replace ignition wires. • Replace spark plugs. • Adjust or replace drive belts. • Change engine oil. • Replace engine oil filter. • Replace fuel filter. (See Note #1) • Lubricate steering linkage. • Drain and refill automatic transmission. • Drain and refill transfer case. 67,500 MILES (108 500 KM) OR AT 54 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Inspect brake linings. 75,000 MILES (120 500 KM) OR AT 60 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage. • Drain and refill manual transmission. • Flush and replace engine coolant if it has been 30,000 miles (48 000 km) or 24 months since last change. 82,500 MILES (133 000 KM) OR AT 66 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4).

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• Flush and replace engine coolant if it has been 30,000 miles (48 000 km) or 24 months since last change.

90,000 MILES (145 000 KM) OR AT 72 MONTHS • Replace air cleaner element. • Replace spark plugs. • Adjust drive belts. • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage. • Inspect brake linings. • Drain and refill automatic transmission. • Drain and refill transfer case. 97,500 MILES (157 000 KM) OR AT 78 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). 105,000 MILES (169 000 KM) OR AT 84 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage. • Flush and replace engine coolant if it has been 30,000 miles (48 000 km) or 24 months since last change. 112,500 MILES (181 000 KM) OR AT 90 MONTHS • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Inspect brake linings. • Drain and refill manual transmission. • Flush and replace engine coolant if it has been 30,000 miles (48 000 km) or 24 months since last change. 120,000 MILES (193 000 KM) OR AT 96 MONTHS • Replace air cleaner element. • Replace distributor cap and rotor. • Lubricate steering linkage. • Drain and refill automatic transmission. • Drain and refill transfer case. • Replace ignition wires. • Replace spark plugs. • Adjust or replace drive belts. • Change engine oil. • Replace engine oil filter. • Replace fuel filter. (See note #1)


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LUBRICATION AND MAINTENANCE

SCHEDULE—B 3,000 MILES (4 800KM) • Change engine oil. • Replace engine oil filter. 6,000 MILES (9 600KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). 9,000 MILES (14 400KM) • Change engine oil. • Replace engine oil filter. 12,000 MILES (19 200KM) • Change engine oil. • Replace engine oil filter. • Drain and refill automatic transmission. • Change front and rear axle fluid.* • Lubricate steering linkage (4x4). • Inspect brake linings. 15,000 MILES (24 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x2). • Inspect air cleaner element, replace as necessary. 18,000 MILES (29 000KM) • Change engine oil. • Replace engine oil filter. • Drain and refill Manual transmission fluid. • Lubricate steering linkage (4x4). 21,000 MILES (34 000KM) • Change engine oil. • Replace engine oil filter. 24,000 MILES (38 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Drain and refill automatic transmission. • Change front and rear axle fluid.* • Inspect brake linings. • Inspect front wheel bearings, Clean and repack if required (4x2). 27,000 MILES (43 000KM) • Change engine oil. • Replace engine oil filter. 30,000 MILES (48 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage joints. • Replace spark plugs. • Replace air cleaner element.

J • Adjust drive belts. • Drain and refill transfer case fluid.

33,000 MILES (53 000KM) • Change engine oil. • Replace engine oil filter. 36,000 MILES (58 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Drain and refill automatic transmission. • Drain and refill manual transmission fluid. • Change front and rear axle fluid.* • Inspect brake linings. 39,000 MILES (62 000KM) • Change engine oil. • Replace engine oil filter. 42,000 MILES (67 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). 45,000 MILES (72 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x2). • Inspect air cleaner element, replace as necessary. 48,000 MILES (77 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Drain and refill automatic transmission. • Change front and rear axle fluid.* • Inspect brake linings. 51,000 MILES (82 000KM) • Change engine oil. • Replace engine oil filter. • Flush and replace engine coolant. 54,000 MILES (86 400KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Drain and refill Manual transmission fluid. 57,000 MILES (91 000KM) • Change engine oil. • Replace engine oil filter. 60,000 MILES (96 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage joints. • Replace spark plugs.


LUBRICATION AND MAINTENANCE

J • • • • • • • • •

Drain and refill automatic transmission fluid. Change front and rear axle fluid.* Replace air cleaner element. Replace distributor cap and rotor. Replace ignition wires. Adjust or replace drive belts. Replace fuel filter. See note #1. Inspect brake linings. Drain and refill transfer case.

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90,000 MILES (144 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage. • Replace spark plugs. • Drain and refill Manual transmission fluid. • Replace air cleaner element. • Adjust drive belts. • Drain and refill transfer case fluid.

63,000 MILES (102 000KM) • Change engine oil. • Replace engine oil filter.

93,000 MILES (149 000KM) • Change engine oil. • Replace engine oil filter.

66,000 MILES (105 600KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4).

96,000 MILES (154 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Drain and refill automatic transmission fluid. • Change front and rear axle fluid.* • Inspect brake linings.

69,000 MILES (110 000KM) • Change engine oil. • Replace engine oil filter. 72,000 MILES (115 200KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Drain and refill Manual transmission fluid. • Drain and refill automatic transmission. • Change front and rear axle fluid.* • Inspect brake linings. 75,000 MILES (120 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x2). • Inspect air cleaner element, replace as necessary. 78,000 MILES (125 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). 81,000 MILES (130 000KM) • Change engine oil. • Replace engine oil filter. • Flush and replace engine coolant. 84,000 MILES (134 400KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Drain and refill automatic transmission fluid. • Change front and rear axle fluid.* • Inspect brake linings. 87,000 MILES (140 000KM) • Change engine oil. • Replace engine oil filter.

99,000 MILES (158 400KM) • Change engine oil. • Replace engine oil filter. 102,000 MILES (163 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). 105,000 MILES (168 000KM) • Change engine oil. • Replace engine oil filter. • Inspect air cleaner element, replace as necessary. • Lubricate steering linkage (4x2). 108,000 MILES (172 800KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). • Drain and refill Manual transmission fluid. • Drain and refill automatic transmission fluid. • Change front and rear axle fluid.* • Inspect brake linings. 111,000 MILES (177 600KM) • Change engine oil. • Replace engine oil filter. • Flush and replace engine coolant. 114,000 MILES (182 400KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4). 117,000 MILES (187 200KM) • Change engine oil. • Replace engine oil filter.


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LUBRICATION AND MAINTENANCE

120,000 MILES (192 000KM) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage. • Replace spark plugs. • Drain and refill automatic transmission fluid. • Change front and rear axle fluid.* • Inspect brake linings. • Replace air cleaner element. • Replace distributor cap and rotor. • Replace ignition wires. • Adjust or replace drive belts. • Replace fuel filter. See note #1.

J • Drain and refill transfer case fluid. NOTE 1: Not required for California vehicles, recommended for proper vehicle performance. * Off-highway operation, trailer towing, taxi, limousine, bus, snow plowing, or other types of commercial service or prolonged operation with heavy loading, especially in hot weather, require front and rear axle service indicated with a * in Schedule—B. Perform these services if you usually operate your vehicle under these conditions. Inspection and service should also be performed anytime a malfunction is observed or suspected.


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JUMP STARTING, TOWING AND HOISTING INDEX page

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Four-Wheel-Drive Vehicle Towing . . . . . . . . . . . . . 12 Ground Clearance and Ramp Angle . . . . . . . . . . . . 11 Hoisting Recommendations . . . . . . . . . . . . . . . . . . 10 Jump Starting Procedure . . . . . . . . . . . . . . . . . . . . . 9

Towing Recommendations . . . . . . . . . . . . . . . . . . . 10 Towing When Keys Are Not Available . . . . . . . . . . 13 Two-Wheel-Drive Vehicle Towing—XJ . . . . . . . . . . 11

JUMP STARTING PROCEDURE

• Fuel fumes or leakage, correct if necessary.

WARNING: DO NOT ATTEMPT TO PUSH OR TOW A VEHICLE TO START THE ENGINE. UNBURNED FUEL COULD ENTER THE EXHAUST CATALYTIC CONVERTER AND IGNITE AFTER THE ENGINE IS STARTED. THIS COULD CAUSE THE CONVERTER TO OVERHEAT AND RUPTURE.

CAUTION: If the cause of starting problem on disabled vehicle is severe, damage to booster vehicle charging system can result.

WARNING: REVIEW ALL SAFETY PRECAUTIONS AND WARNINGS IN GROUP 8A, BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS. DO NOT JUMP START A FROZEN BATTERY, PERSONAL INJURY CAN RESULT. DO NOT JUMP START WHEN MAINTENANCE FREE BATTERY INDICATOR DOT IS YELLOW OR BRIGHT COLOR. DO NOT JUMP START A VEHICLE WHEN THE BATTERY FLUID IS BELOW THE TOP OF LEAD PLATES. DO NOT ALLOW JUMPER CABLE CLAMPS TO TOUCH EACH OTHER WHEN CONNECTED TO A BOOSTER SOURCE. DO NOT USE OPEN FLAME NEAR BATTERY. REMOVE METALLIC JEWELRY WORN ON HANDS OR WRISTS TO AVOID INJURY BY ACCIDENTAL ARCING OF BATTERY CURRENT. WHEN USING A HIGH OUTPUT BOOSTING DEVICE, DO NOT ALLOW BATTERY VOLTAGE TO EXCEED 16 VOLTS. REFER TO INSTRUCTIONS PROVIDED WITH DEVICE BEING USED.

(2) When using another vehicle as a booster source, turn off all accessories, place gear selector in park or neutral, set park brake and operate engine at 1200 rpm. (3) On disabled vehicle, place gear selector in park or neutral and set park brake. Turn off all accessories. (4) Connect jumper cables to booster battery. RED clamp to positive terminal (+). BLACK clamp to negative terminal (-). DO NOT allow clamps at opposite end of cables to touch, electrical arc will result. Review all warnings in this procedure. (5) On disabled vehicle, connect RED jumper cable clamp to positive (+) terminal. Connect BLACK jumper cable clamp to engine ground as close to the ground cable attaching point as possible (Fig. 1).

CAUTION: When using another vehicle as a booster, do not allow vehicles to touch. Electrical systems can be damaged on either vehicle.

TO JUMP START A DISABLED VEHICLE: (1) Raise hood on disabled vehicle and visually inspect engine compartment for: • Battery cable clamp condition, clean if necessary. • Frozen battery. • Yellow or bright color test indicator, if equipped. • Low battery fluid level. • Generator drive belt condition and tension.

Fig. 1 Jumper Cable Connections—Typical


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CAUTION: Do not crank starter motor on disabled vehicle for more than 15 seconds, starter will overheat and could fail. (6) Allow battery in disabled vehicle least 12.4 volts (75%charge) before start engine. If engine does not start onds, stop cranking engine and allow (15 min.), before cranking again.

to charge to at attempting to within 15 secstarter to cool

DISCONNECT CABLE CLAMPS AS FOLLOWS: • Disconnect BLACK cable clamp from engine ground on disabled vehicle. • When using a Booster vehicle, disconnect BLACK cable clamp from battery negative terminal. Disconnect RED cable clamp from battery positive terminal. • Disconnect RED cable clamp from battery positive terminal on disabled vehicle.

PORTABLE STARTING UNIT There are many types of portable starting units available for starting engines. Follow the manufacturer’s instructions and observe the listed precautions when involved in any engine starting procedure.

HOISTING RECOMMENDATIONS Refer to the Owner’s Manual for emergency vehicle lifting procedures.

FLOOR JACK When properly positioned, a floor jack can be used to lift a Jeep vehicle (Fig. 2 and 3). Support the vehicle in the raised position with jack stands at the front and rear ends of the frame rails. CAUTION: Do not attempt to lift a Jeep vehicle with a floor jack positioned under: • • • • • • •

Fig. 2 Vehicle Lifting Locations—Typical WARNING: THE HOISTING AND JACK LIFTING POINTS PROVIDED ARE FOR A COMPLETE VEHICLE. WHEN A CHASSIS OR DRIVETRAIN COMPONENT IS REMOVED FROM A VEHICLE, THE CENTER OF GRAVITY IS ALTERED MAKING SOME HOISTING CONDITIONS UNSTABLE. PROPERLY SUPPORT OR SECURE VEHICLE TO HOISTING DEVICE WHEN THESE CONDITIONS EXIST.

TOWING RECOMMENDATIONS

An axle tube. A body side sill. A steering linkage component. A drive shaft. The engine or transmission oil pan. The fuel tank. A front suspension arm. Use the correct sub-frame rail or frame rail lifting locations only (Fig. 2 and 3).

A vehicle equipped with SAE approved sling-type towing equipment can be used to tow all Jeep vehicles. When towing a 4WD vehicle using a wheel-lift towing device, use a tow dolly under the opposite end of the vehicle. A vehicle with flat-bed device can also be used to transport a disabled vehicle (Fig. 4). A wooden crossbeam may be required for proper connection when using the sling-type, front-end towing method.

HOIST A vehicle can be lifted with: • A single-post, frame-contact hoist. • A twin-post, chassis hoist. • A ramp-type, drive-on hoist. When a frame-contact type hoist is used, verify that the lifting pads are positioned properly (Fig. 2 and 3).

SAFETY PRECAUTIONS • Secure loose and protruding parts. • Always use a safety chain system that is independent of the lifting and towing equipment. • Do not allow towing equipment to contact the disabled vehicle’s fuel tank. • Do not allow anyone under the disabled vehicle while it is lifted by the towing device.


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• Do not tow a vehicle in a manner that could jeopardize the safety of the operator, pedestrians or other motorists. • Do not attach tow chains, T-hooks, J-hooks, or a tow sling to a bumper, steering linkage, drive shafts or a non-reinforced frame hole.

GROUND CLEARANCE AND RAMP ANGLE GROUND CLEARANCE CAUTION: If vehicle is towed with wheels removed, install lug nuts to retain brake drums. A towed vehicle should be raised until lifted wheels are a minimum 100 mm (4 in) from the ground. Be sure there is adequate ground clearance at the opposite end of the vehicle, especially when towing over rough terrain or steep rises in the road. If necessary, remove the wheels from the lifted end of the vehicle and lower the vehicle closer to the ground, to increase the ground clearance at the opposite end of the vehicle. Install lug nuts on wheel attaching studs to retain brake drums.

Fig. 3 Correct Vehicle Lifting Locations—Typical

FLAT-BED TOWING RAMP ANGLE If a vehicle with flat-bed towing equipment is used, the approach ramp angle should not exceed 15 degrees.

TWO-WHEEL-DRIVE VEHICLE TOWING—XJ Chrysler Corporation recommends that a vehicle be towed with the rear end lifted, whenever possible.

TOWING-REAR END LIFTED (SLING-TYPE) CAUTION: Do not use steering column lock to secure steering wheel during towing operation.

Fig. 4 Tow Vehicles With Approved Equipment. • Do not allow passengers to ride in a vehicle being towed. • Always observe state and local laws regarding towing regulations.

2WD XJ vehicles can be towed with the front wheels on the surface for extended distances at speeds not exceeding 48 km/h (30 mph). (1) Attach J-hooks around the axle shaft tube outboard of the shock absorber. (2) Place the sling crossbar under and forward of the bumper. (3) Attach safety chains around the frame rails. (4) Turn the ignition switch to the OFF position to unlock the steering wheel. (5) Secure steering wheel in the straight ahead position with a clamp device designed for towing. (6) Verify that steering components are in good condition. (7) Shift the transmission to NEUTRAL.


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TOWING-FRONT END LIFTED (SLING-TYPE)

TOWING-REAR END LIFTED (SLING-TYPE)

CAUTION: Many vehicles are equipped with air dams, spoilers, and/or ground effect panels. To avoid component damage, a wheel-lift towing vehicle or a flat-bed hauling vehicle is recommended.

4WD XJ VEHICLES (1) Raise the front of the vehicle off the ground and install tow dollies under front wheels. (2) Attach J-hooks around the rear axle shaft tube outboard of the shock absorber. (3) Place the sling crossbar under and forward of the bumper. (4) Attach safety chains around the frame rails. (5) Turn the ignition switch to the OFF position to unlock the steering wheel. (6) Secure steering wheel in the straight ahead position with a clamp device designed for towing. (7) Shift the transfer case to NEUTRAL.

If a 2WD XJ vehicle cannot be towed with the rear wheels lifted, it can be towed with the front wheels lifted. (1) Attach a J-hook to the disabled vehicle at the left side of the axle. (2) Position the sling crossbar close to the J-hook and below the front bumper. (3) Secure a chain to the right side of vehicle by placing it over the axle shaft tube and attaching it to a structural member (Fig. 5). (4) Attach the safety chains to the vehicle. (5) Turn the ignition switch to the OFF position to unlock the steering wheel.

4WD YJ VEHICLES Use Wheel-Lift equipment and Tow Dollies when towing from the rear end of the vehicle.

TOWING-FRONT END LIFTED (SLING-TYPE)

Fig. 5 Sling-Type, Front-End Towing (XJ Rear View)

4WD XJ VEHICLES (1) Raise the rear of the vehicle off the ground and install tow dollies under rear wheels. (2) Attach a J-hook to the disabled vehicle at the left side of front the axle. (3) Position the sling crossbar close to the J-hook and below the front bumper (Fig. 6). (4) Secure a chain to the right side of vehicle by placing it over the axle shaft tube and attaching it to a structural member (4) Attach the safety chains to the vehicle. (5) Turn the ignition switch to the OFF position to unlock the steering wheel. (6) Shift transfer case to NEUTRAL.

2WD-AUTOMATIC TRANSMISSION Provided the transmission is operable, tow only in NEUTRAL at speeds not to exceed 30 mph (50 km/h) and distances less than 15 miles (25km/h). If the vehicle is to be towed more than 15 miles, the propeller shaft should be disconnected or place tow dollies under rear wheels. 2WD-MANUAL TRANSMISSION To reduce the possible damage of transmission components, the propeller shaft must be removed or place tow dollies under the rear wheels before towing. Refer to Propeller Shafts, Group 16 for proper removal procedure.

FOUR-WHEEL-DRIVE VEHICLE TOWING Chrysler Corporation recommends that a vehicle be transported on a flat-bed device. A Wheel-lift or Sling-type device can be used provided all the wheels are lifted off the ground using tow dollies.

Fig. 6 Sling-Type, Front-End Towing (XJ Front View)


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4WD YJ VEHICLES (1) Raise the rear of the vehicle off the ground and install tow dollies under rear wheels. CAUTION: Use tow chains with T-hooks for connecting to the disabled vehicle’s frame rails. Never use J-hooks. (2) Attach the T-hooks to the slots in the front end of each frame rail (Fig. 7). (3) Position each safety chain over the top of each front spring and inboard of each front spring shackle. (4) Double wrap each chain. (5) Position the sling crossbar under the front bumper. (6) Turn the ignition switch to the OFF position to unlock the steering wheel. (7) Shift the transfer case to NEUTRAL.

Fig. 8 Sling-Type, Front-End Towing With Rear Wheels On A Tow Dolly CAUTION: DO NOT use emergency tow hooks for tow truck hook-up or highway towing.

Fig. 7 Sling-Type, Front-End Towing (YJ Vehicles)

TOWING WHEN KEYS ARE NOT AVAILABLE When the vehicle is locked and keys are not available, use a flat bed hauler. A Wheel-lift or Sling-type device can be used provided all the wheels are lifted off the ground using tow dollies (Fig. 8).

EMERGENCY TOW HOOKS WARNING: REMAIN AT A SAFE DISTANCE FROM A VEHICLE THAT IS BEING TOWED VIA ITS TOW HOOKS. THE TOW STRAPS/CHAINS COULD BREAK AND CAUSE SERIOUS INJURY. Some Jeep vehicles are equipped with front and rear emergency tow hooks (Fig. 9). The tow hooks should be used for EMERGENCY purposes only.

Fig. 9 Emergency Front Tow Hooks—XJ & YJ Vehicles FLAT TOWING (4 TIRES/WHEELS ON SURFACE) Tow a vehicle in this manner only when all four wheels will freely rotate. Prepare the vehicle according to the following procedures. 2WD VEHICLES (1) Mark the drive shaft and the axle drive pinion gear shaft yoke for installation alignment reference. (2) Remove the drive shaft. Install a protective covering over the drive shaft U-joints to retain them assembled and protected.


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(3) Cover the open end of the transmission extension housing. 4WD VEHICLES—XJ (1) Shift transfer case lever to NEUTRAL. (2) Place ignition switch in the unlocked position. 4WD VEHICLES—YJ CAUTION: Follow these steps to be certain that the transfer case is fully in N (NEUTRAL) and that the axle is completely disengaged before flat towing to prevent damage to internal parts. (1) Shift transfer case into 2H and check that the 4WD light goes out. (2) Start engine and drive the vehicle 3 mm (10 ft.) rearward and then 3 mm (10 ft.) forward to make sure the axle is disengaged.

J (3) Shift transmission to Neutral. (4) Turn off engine with the ignition key in the unlocked OFF position. (5) Shift transfer case lever from 2H to N (NEUTRAL) position. (6) Shift manual transmission into gear or automatic transmission into P (PARK). WARNING: WITH THE TRANSFER CASE IN NEUTRAL POSITION, THE VEHICLE COULD ROLL UNEXPECTEDLY. THE PARKING BRAKE SHOULD ALWAYS BE APPLIED BEFORE THE TOW BAR IS ATTACHED. (7) Attach vehicle to the tow vehicle with tow bar. CAUTION: Do not use a bumper mounted clamp-on tow bar, damage to bumper face bar may occur.


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ENGINE MAINTENANCE INDEX page Accessory Drive Belt . . . . . . . Air Cleaner Element . . . . . . . Air-Conditioner Compressor . . Battery . . . . . . . . . . . . . . . . . Crankcase Ventilation System Emission Control System . . . Engine Break-In . . . . . . . . . . Engine Cooling System . . . . . Engine Oil . . . . . . . . . . . . . .

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page Engine Oil Change and Filter Replacement Engine Oil Filter . . . . . . . . . . . . . . . . . . . Engine Supports . . . . . . . . . . . . . . . . . . . Exhaust System . . . . . . . . . . . . . . . . . . . Fuel Filter . . . . . . . . . . . . . . . . . . . . . . . . Fuel Usage Statement—Gas Engines . . . Ignition Cables, Distributor Cap and Rotor Rubber and Plastic Component Inspection Spark Plugs . . . . . . . . . . . . . . . . . . . . . .

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ENGINE BREAK-IN

ENGINE OIL SPECIFICATION

CAUTION: Wide open throttle operation in low gears, before engine break-in period is complete, can damage engine.

CAUTION: Do not use non-detergent or straight mineral oil when adding or changing crankcase lubricant. Engine failure can result.

After first starting a new engine, allow it to idle for 15 seconds before shifting into a drive gear. Also: • Drive the vehicle at varying speeds less than 88 km/h (55 mph) for the first 480 km (300 miles). • Avoid fast acceleration and sudden stops. • Do not drive at full-throttle for extended periods of time. • Do not drive at constant speeds. • Do not idle the engine excessively. A special break-in engine oil is not required. The original engine oil installed is a high quality, energy conserving lubricant. Special break-in oils are not recommended. These oils could interfere with the normal piston ring seating process. New engines tend to consume more fuel and oil until after the break-in period has ended.

API SERVICE GRADE CERTIFIED Use an engine oil that is API Service Grade Certified or an oil that conforms to the API Service Grade SH or SH/CD. MOPAR provides engine oils that conform to all of these service grades. SAE VISCOSITY An SAE viscosity grade is used to specify the viscosity grade of engine oil. SAE 30 specifies a single viscosity engine oil. Engine oils also have multiple viscosities. These are specified with a dual SAE viscosity grade which indicates the cold-to-hot temperature viscosity range. Select an engine oil that is best suited to your particular temperature range and variation (Fig.1).

ENGINE OIL WARNING: NEW OR USED ENGINE OIL CAN BE IRRITATING TO THE SKIN. AVOID PROLONGED OR REPEATED SKIN CONTACT WITH ENGINE OIL. CONTAMINANTS IN USED ENGINE OIL, CAUSED BY INTERNAL COMBUSTION, CAN BE HAZARDOUS TO YOUR HEALTH. THOROUGHLY WASH EXPOSED SKIN WITH SOAP AND WATER. DO NOT WASH SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO NOT POLLUTE, DISPOSE OF USED ENGINE OIL PROPERLY. CONTACT YOUR DEALER OR GOVERNMENT AGENCY FOR LOCATION OF COLLECTION CENTER IN YOUR AREA.

Fig. 1 Temperature/Engine Oil Viscosity ENERGY CONSERVING OIL An Energy Conserving type oil is recommeded for gasoline engines. They are designated as either ENERGY CONSERVING or ENERGY CONSERVING II.


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CONTAINER IDENTIFICATION Standard engine oil identification notations have been adopted to aid in the proper selection of engine oil. The identifying notations are located on the label of engine oil plastic bottles and the top of engine oil cans (Fig. 2).

Fig. 2 API Certification Mark ENGINE OIL ADDITIVES In some instances, such as infrequent operation, short trip driving, and during break-in after a major overhaul, addition of special materials containing anti-rust and anti-scuff additives are beneficial. A suitable product for this purpose is MOPAR Engine Oil Supplement.

J CRANKCASE OIL LEVEL INSPECTION CAUTION: Do not overfill crankcase with engine oil, oil foaming and oil pressure loss can result. Inspect engine oil level approximately every 800 kilometers (500 miles). Unless the engine has exhibited loss of oil pressure, run the engine for about five minutes before checking oil level. Checking engine oil level on a cold engine is not accurate. To ensure proper lubrication of an engine, the engine oil must be maintained at an acceptable level. The acceptable levels are indicated between the ADD and SAFE marks on the engine oil dipstick (Fig. 4 and 5). (1) Position vehicle on level surface. (2) With engine OFF, allow approximately ten minutes for oil to settle to bottom of crankcase, remove engine oil dipstick. (3) Wipe dipstick clean. (4) Install dipstick and verify it is seated in the tube. (5) Remove dipstick, with handle held above the tip, take oil level reading (Figs.4 and 5). (6) Add oil only if level is below the ADD mark on dipstick.

OIL LEVEL INDICATOR (DIPSTICK) The engine oil level indicator (Dipstick) is located at the right rear of both 2.5L engines and 4.0L engines (Fig. 3).

Fig. 4 Engine Oil Dipstick—2.5L Engine

ENGINE OIL CHANGE AND FILTER REPLACEMENT ENGINE OIL CHANGE Change engine oil at mileage and time intervals described in Maintenance Schedules.

Fig. 3 Engine Oil Dipstick Location—Typical

TO CHANGE ENGINE OIL Run engine until achieving normal operating temperature. (1) Position the vehicle on a level surface and turn engine off. (2) Hoist and support vehicle on safety stands. Refer to Hoisting and Jacking Recommendations in this group.


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Fig. 5 Engine Oil Dipstick — 4.0L Engine

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Fig. 6 Oil Filter—2.5L Engine

(3) Remove oil fill cap. (4) Place a suitable drain pan under crankcase drain. (5) Remove drain plug from crankcase and allow oil to drain into pan. Inspect drain plug threads for stretching or other damage. Replace drain plug and gasket if damaged. (6) Install drain plug in crankcase. (7) Lower vehicle and fill crankcase with specified type and amount of engine oil described in this section. (8) Install oil fill cap. (9) Start engine and inspect for leaks. (10) Stop engine and inspect oil level.

ENGINE OIL FILTER FILTER SPECIFICATION CAUTION: Do not use oil filter with metric threads. The proper oil filter has SAE type 3/4 X 16 threads. An oil filter with metric threads can result in oil leaks and engine failure. All Jeep engines are equipped with a high quality full-flow, throw-away type oil filter. Chrysler Corporation recommends a Mopar or equivalent oil filter be used.

OIL FILTER REMOVAL (1) Position a drain pan under the oil filter. (2) Using a suitable oil filter wrench loosen filter. (3) Rotate the oil filter counterclockwise to remove it from the cylinder block oil filter boss (Fig. 6 and 7). (4) When filter separates from adapter nipple, tip gasket end upward to minimize oil spill. Remove filter from vehicle. (5) With a wiping cloth, clean the gasket sealing surface (Fig. 8) of oil and grime.

Fig. 7 Oil Filter — 4.0L Engine OIL FILTER INSTALLATION (1) Lightly lubricate oil filter gasket with engine oil or chassis grease. (2) Thread filter onto adapter nipple. When gasket makes contact with sealing surface, (Fig. 8) hand tighten filter one full turn, do not over tighten. (3) Add oil, verify crankcase oil level and start engine. Inspect for oil leaks.

Fig. 8 Oil Filter Sealing Surface—Typical


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LUBRICATION AND MAINTENANCE

USED ENGINE OIL DISPOSAL Care should be exercised when disposing used engine oil after it has been drained from a vehicle engine. Refer to the WARNING listed above.

ENGINE COOLING SYSTEM WARNINGS AND PRECAUTIONS WARNING: ANTIFREEZE IS AN ETHYLENE GLYCOL BASE COOLANT AND IS HARMFUL IF SWALLOWED OR INHALED. IF SWALLOWED, DRINK TWO GLASSES OF WATER AND INDUCE VOMITING. IF INHALED, MOVE TO FRESH AIR AREA. SEEK MEDICAL ATTENTION IMMEDIATELY. DO NOT STORE IN OPEN OR UNMARKED CONTAINERS. WASH SKIN AND CLOTHING THOROUGHLY AFTER COMING IN CONTACT WITH ETHYLENE GLYCOL. KEEP OUT OF REACH OF CHILDREN. DISPOSE OF GLYCOL BASE COOLANT PROPERLY, CONTACT YOUR DEALER OR GOVERNMENT AGENCY FOR LOCATION OF COLLECTION CENTER IN YOUR AREA. DO NOT OPEN A COOLING SYSTEM WHEN THE ENGINE IS AT RUNNING TEMPERATURE, PERSONAL INJURY CAN RESULT. AVOID RADIATOR COOLING FAN WHEN ENGINE COMPARTMENT RELATED SERVICE IS PERFORMED, PERSONAL INJURY CAN RESULT. CAUTION: Do not use straight antifreeze as engine coolant, inadequate engine running temperatures can result. Do not operate vehicle without proper concentration of recommended ethylene glycol coolant, high running temperatures and cooling system corrosion can result. The engine cooling system will develop internal pressure of 97 to 123 kPa (14 to 18 psi) at normal operating temperature. Allow the vehicle approximately one half hour to cool off before opening the cooling system. As an indicator of pressure, squeeze the upper radiator hose between index finger and thumb. If it collapses with little effort the system would have low internal pressure and should be safe to open to the first safety notch of the radiator cap. Refer to Group 7, Cooling System.

COOLING SYSTEM INSPECTION Coolant level should be inspected when other engine compartment service is performed or when coolant leak is suspected. With the engine at normal operating temperature, observe the coolant level in the coolant recovery bottle. The coolant level must

J be at least above the ADD mark and preferably at the FULL mark. Add coolant to the coolant recovery bottle only, if necessary. Cooling system freeze protection should be tested at the onset of the winter season or every 12 months. Service is required if coolant is low, contaminated, rusty or freeze protection is inadequate. To properly test cooling system, see Group 7, Cooling System. The cooling system factory fill is a mixture of 50% Ethylene Glycol based antifreeze and 50% water. Using a suitable hydrometer, measure antifreeze concentration in the radiator when the engine is cool. If the cooling system has recently been serviced, allow coolant to circulate for at least 20 minutes before taking hydrometer reading. Properly mixed coolant will protect the cooling system to -37째C (-35째F). If the freeze protection is above -28째C (-20째F), drain enough coolant from the cooling system to allow room to add antifreeze to achieve adequate protection. A mix table on the coolant container indicates the amount of antifreeze required to winterize the cooling system based on the capacity, see Capacity Chart in General Information section of this group.

ANTIFREEZE SPECIFICATION Chrysler Corporation recommends the use of Mopar Antifreeze/Coolant or a high quality, ethylene glycol base antifreeze/coolant, with a silicate inhibitor. COOLING SYSTEM SERVICE The cooling system should be drained, flushed and filled with the proper coolant mixture at the intervals described in the Lubrication and Maintenance Schedules. Refer to General Information section of this group. For proper service instructions see Group 7, Cooling System.

AIR CLEANER ELEMENT The air cleaner element should be serviced at the intervals described in the Lubrication and Maintenance Schedules sections of this group. Additional information can be found in Group 14, Fuel System and Group 25, Emission System. Inspect all air cleaner hoses or tubes for damage or leaks when other engine compartment service is performed. Replace faulty components.

FILTER ELEMENT SERVICE/REPLACEMENT CAUTION: The air cleaner cover must be installed properly for the emissions system and engine controller to function correctly. Do not immerse paper air filter element in cleaning solvents, damage can result. (1) Remove the air cleaner cover from the body/ housing (Fig. 9).


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CRANKCASE VENTILATION SYSTEM All Jeep 2.5L and 4.0L engines are equipped with a crankcase ventilation (CCV) system. Refer to Group 25 Emissions, for additional information.

FUEL FILTER The fuel filter requires service only when a fuel contamination problem is suspected. For proper diagnostic and service procedures refer to Group 14, Fuel System.

FUEL USAGE STATEMENT—GAS ENGINES

Fig. 9 Air Cleaner & Filter Element—2.5L and 4.0L Engines (2) Remove the air cleaner element from the body/ housing. (3) Hold a shop light on throttle body side of element. Inspect air intake side of element. If element is saturated with oil or light is not visible, replace filter. If element is saturated with oil, perform crankcase ventilation system tests. (4) Wash the air cleaner cover and body/housing (Fig. 10) with cleaning solvent and wipe dry.

Jeep vehicles are designed to meet all emission regulations and provide excellent fuel economy using high quality unleaded gasoline. Only use unleaded gasolines having a minimum posted octane of 87. If a Jeep vehicle develops occasional light spark knock (ping) at low engine speeds, this is not harmful. However, continued heavy knock at high speeds can cause damage and should be checked immediately. In addition to using unleaded gasoline with the proper octane rating, those that contain detergents, corrosion and stability additives are recommended. Using gasolines that have these additives will help improve fuel economy, reduce emissions and maintain vehicle performance. Poor quality gasoline can cause problems such as hard starting, stalling and stumble. If these problems occur, use another brand of gasoline before considering servicing the vehicle.

GASOLINE/OXYGENATE BLENDS Some fuel suppliers blend unleaded gasoline with materials that contain oxygen such as alcohol, MTBE and ETBE. The type and amount of oxygenate used in the blend is important. The following are generally used in gasoline blends: ETHANOL Ethanol (Ethyl or Grain Alcohol) properly blended, is used as a mixture of 10 percent ethanol and 90 percent gasoline. Gasoline with ethanol may be used in your vehicle. METHANOL

Fig. 10 Air Cleaner Body/Housing & Cover (5) Install the air cleaner element and attach the cover to the body/housing.

CAUTION: Do not use gasolines containing methanol. Use of methanol/gasoline blends may result in starting and driveability problems. In addition, damage may be done to critical fuel system components. Methanol (Methyl or Wood Alcohol) is used in a variety of concentrations blended with unleaded gaso-


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LUBRICATION AND MAINTENANCE

line. You may encounter fuels containing 3 percent or more methanol along with other alcohols called cosolvents. Problems that are the result of using methanol/gasoline blends are not the responsibility of Chrysler Corporation. They may not be covered by the vehicle warranty. MTBE/ETBE Gasoline and MTBE (Methyl Tertiary Butyl Ether) blends are a mixture of unleaded gasoline and up to 15 percent MTBE. Gasoline and ETBE (Ethyl Tertiary Butyl Ether) are blends of gasoline and up to 17 percent ETBE. Gasoline blended with MTBE or ETBE may be used. CLEAN AIR GASOLINE Many gasolines are now being blended that contribute to cleaner air, especially in those areas of the country where air pollution levels are high. These new blends provide a cleaner burning fuel and some are referred to as Reformulated Gasoline. In areas of the country where carbon monoxide levels are high, gasolines are being treated with oxygenated materials such as MTBE, ETBE and ethanol. Chrysler Corporation supports these efforts toward cleaner air and recommends the use of these gasolines as they become available.

J DLING/SERVICING A BATTERY. THE BATTERY ELECTROLYTE CONTAINS SULFURIC ACID AND WILL CAUSE HARM IF IT CONTACTS SKIN, EYES OR CLOTHING. IT WILL ALSO DAMAGE PAINTED (AS WELL AS UN-PAINTED) SURFACES OF A VEHICLE. IF SULFURIC ACID CONTACTS ANY OF THESE, FLUSH IMMEDIATELY WITH LARGE AMOUNTS OF WATER. IF SULFURIC ACID CONTACTS SKIN OR EYES, GET IMMEDIATE MEDICAL ATTENTION. DO NOT SMOKE IN THE VICINITY OF A BATTERY. KEEP OPEN FLAMES AND SPARKS AWAY FROM BATTERY FILLER CAPS BECAUSE EXPLOSIVE GAS IS ALWAYS PRESENT. Inspect battery tray, hold down and terminal connections when other under hood service is performed. For proper diagnostic procedures refer to Group 8A, Battery/Starting/Charging System Diagnostics. For service and cleaning procedures refer to Group 8B, Battery/Starter Service. Care should be taken when disposing a battery after removal from a vehicle. Lead-acid batteries are highly poisonous and, when indiscriminately disposed, could create a problem for the environment. Contact the applicable local city or county government agency to determine where automobile (lead-acid) batteries can be properly disposed in the local area.

IGNITION CABLES, DISTRIBUTOR CAP AND ROTOR

RUBBER AND PLASTIC COMPONENT INSPECTION

Inspect and test ignition cables, distributor cap and rotor when the spark plugs are replaced. Oil and grime should be cleaned from the ignition cables and distributor cap to avoid possible spark plug fouling. Mopar Foamy Engine Degreaser or equivalent is recommended for cleaning the engine compartment. For proper service and diagnostic procedures refer to Group 8D, Ignition System.

CAUTION: Plastic hoses or wire harness covers will melt or deform when exposed to heat from exhaust system or engine manifolds. Position plastic or rubber components away from moving parts in engine compartment or under vehicle, or damage will result. Do not allow rubber engine mounts or other components to become oil contaminated, repair cause of oil contamination and clean area.

IGNITION TIMING The ignition timing for 2.5L and 4.0L engines is not adjustable. Refer to the specifications listed on the engine Emission Control Information Label. Refer to Group 25, Emission Control Systems for additional information.

SPARK PLUGS Ignition spark plugs should be replaced at the mileage interval described in the Lubrication and Maintenance Schedules. Refer to the General Information section of this group. For proper service procedures refer to Group 8D, Ignition Systems.

BATTERY WARNING: WEAR SAFETY GLASSES, RUBBER GLOVES AND PROTECTIVE CLOTHING WHEN HAN-

All rubber and plastic components should be inspected when engine compartment or under vehicle service is performed. When evidence of deterioration exists, replacement is required. To reduce deterioration of rubber components, Chrysler Corporation recommends Mopar Foamy Engine Degreaser or equivalent be used to clean engine compartment of oil and road grime.

EMISSION CONTROL SYSTEM Inspect all emission control components and hoses when other under hood service is performed. Refer to emission system Vacuum Hose Label located on the inside of the hood in the engine compartment and Group 25, Emission Control Systems for proper service procedures.


LUBRICATION AND MAINTENANCE

J ENGINE SUPPORTS The general condition of the engine supports should be inspected when engine compartment or under vehicle service is performed.

INSPECTION (1) Test the hardware that attaches the engine cylinder block to the engine support brackets (Figs. 11 and 12) for the specified tightening torque.

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(2) Inspect the rubber in the engine support cushions for softening and swelling. Slight surface deterioration and wear at the ends will not affect the functioning of an engine support.

ACCESSORY DRIVE BELT Inspect and adjust drive belts at the interval described in the Lubrication and Maintenance Schedules. Refer to General Information section of this group. For proper inspection and adjustment procedures, see Group 7, Cooling System.

EXHAUST SYSTEM The exhaust system should be inspected when under vehicle service is performed or as specified in the Lubrication and Maintenance Schedules.

Fig. 11 Front Engine Support—Typical

INSPECTION When inspecting an exhaust system, inspect for cracked or loose joints, stripped screw/bolt threads, corrosion damage, and worn or broken hangers (Slight cracking in rubber isolator or hanger is acceptable). Replace all components that are corroded or damaged. Do not attempt repair. Also, inspect for the following obvious conditions and correct as necessary: • Exhaust system leaks, damage, misalignment. • Contact with body panels metal or the frame. • Catalytic converter bulging or excessive heat damage. CAUTION: A catalytic converter will become contaminated if leaded gasoline is burned in the engine. If this occurs, the complete converter must be replaced. For proper service procedures see Group 11, Exhaust System and Intake Manifold.

AIR-CONDITIONER COMPRESSOR

Fig. 12 Rear Engine Support—Typical

LUBRICANT AND REFRIGERANT The lubricant level in the air-conditioner compressor should be checked if there are indications that oil was lost. Loss of lubricating oil usually accompanies a loss of refrigerant. For additional information involving the A/C system, refer to Group 24, Heater And Air Conditioning.


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DRIVETRAIN INDEX page Automatic Transmission . . . . . . Clutch and Brake Pedal Bushings Clutch Master Cylinder . . . . . . . Drive Shafts . . . . . . . . . . . . . . .

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CLUTCH AND BRAKE PEDAL BUSHINGS If the clutch and brake pedal mechanism squeaks, the pivot bushings should be lubricated. Use Mopar Multi-Purpose Lubricant, or an equivalent. Refer to Group 5, Brakes for location of bushings.

CLUTCH MASTER CYLINDER LEVEL INSPECTION WARNING: DO NOT ALLOW PETROLEUM OR WATER BASE LIQUIDS TO CONTAMINATE CLUTCH FLUID, SEAL DAMAGE AND CLUTCH FAILURE CAN RESULT. The clutch reservoir level should be inspected when other underhood service is performed. (Fig. 1)

Fig. 2 Hydraulic Clutch Fluid Level—Typical CAUTION: Never use reclaimed brake fluid or fluid from an unsealed container. In addition, do not use fluid from a container that has been opened and allowed to stand for an extended length of time. Moisture in the air can be absorbed by the fluid, which causes dilution with loss of effectiveness.

MANUAL TRANSMISSION The manual transmission should be inspected for oil leaks and proper oil level when other under vehicle service is performed.

Fig. 1 Clutch Reservoir Location—Typical The fluid level is determined by its height in relation to the level indicator ring (Fig. 2) located inside the reservoir. Add fluid until the height is level with the indicator ring.

FLUID SPECIFICATION Use Mopar, Brake And Hydraulic Clutch Fluid or equivalent. Use only brake fluid conforming to DOT 3, Federal, Department of Transportation specification. To avoid fluid contamination, use fluid from a properly sealed container.

LUBRICANT SPECIFICATION When it becomes necessary to add to or change the lube oil in a Jeep manual transmission, use SAE 75W-90, API Quality Grade GL-5 gear lubricant. LUBRICANT LEVEL The fill-hole plug for all manual transmissions is located on the right side of the case (Fig. 3). Determine the lubricant level according to the following procedure. (1) Remove the fill-hole plug (Fig. 3) from the transmission. The lube oil should be level with the bottom edge of the fill hole. The level can be slightly below the bottom edge of the fill hole if the lube oil is cold.


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other under hood service is performed. Refer to Group 21, Transmission for proper service procedures. CAUTION: To minimize fluid contamination, verify that dipstick is seated in the fill tube after fluid level reading is taken.

TO INSPECT THE TRANSMISSION FLUID LEVEL

Fig. 3 Manual Transmission Fill- & Drain-Hole Plugs—Typical If the transmission is warm, lube oil could drip out of the fill hole. This is acceptable but the lube oil should not gush out of the fill hole. (2) If not acceptable, raise the lube oil level to the bottom edge of the transmission fill hole. Add lube oil in small amounts to raise the level. (3) Install the fill-hole plug in the transmission. Tighten the plug with 37 Nzm (27 ft. lbs.) torque.

LUBE OIL CHANGE When it becomes necessary to change manual transmission lube oil, use the following procedure. (1) Raise and support the vehicle. (2) Remove the fill-hole plug from the transmission. (3) Place a container to collect the lube oil under the transmission drain-hole plug. (4) Remove the drain-hole plug and drain the lube oil from the transmission into the container. Care should be exercised when disposing used lube oil after it has been drained from a transmission. (5) Install the drain-hole plug in the transmission. Tighten the plug with 37 Nzm (27 ft. lbs.) torque. (6) Fill the transmission until the lube oil begins to drip out of the fill hole. (7) Install the fill-hole plug in the transmission. Tighten the plug with 37 Nzm (27 ft. lbs.) torque. (8) Remove the support and lower the vehicle.

AUTOMATIC TRANSMISSION The automatic transmission fluid should be changed and bands adjusted at the intervals described in the Maintenance Schedules section of this Group. The automatic transmission should be inspected for fluid leaks and proper fluid level when

WARNING: USE EXTREME CAUTION WHEN THE ENGINE IS OPERATING. DO NOT PUT YOUR HANDS NEAR THE DRIVE BELT, PULLEYS OR FAN BLADE. DO NOT STAND IN A DIRECT LINE WITH THE FAN BLADE. (1) Be sure transmission fluid is at normal operating temperature. Normal operating temperature is reached after approximately 15 miles (25km) of operation. (2) Position the vehicle on a level surface. This is important for an accurate fluid level check. (3) While sitting in driver seat, apply brakes and place gear selector in each position, then move the selector to: • XJ vehicles-P (Park). • YJ vehicles-N (Neutral). (4) Apply parking brake. (5) Raise hood and wipe off dipstick handle to prevent dirt from entering fill tube. Then remove transmission fluid level indicator (dipstick) and wipe clean with a wiping cloth. (6) Install dipstick and verify it is seated in fill hole or tube. (7) Remove dipstick, with handle above tip, take fluid level reading. If the vehicle has been driven for at least 15 minutes before inspecting fluid level, transmission can be considered hot and reading should be in the OK area. If vehicle has run for less than 15 minutes and more than 60 seconds transmission can be considered warm and reading should be above MIN mark. Add fluid only if level is below MIN mark on dipstick when transmission is warm (Fig. 4). CAUTION: Do not overfill automatic transmission, leakage or damage can result.

AUTOMATIC TRANSMISSION FLUID SPECIFICATION When it becomes necessary to add fluid or when the ATF is replaced, use: • MOPAR Dexron IIE/Mercon ATF only for AW-4 automatic transmissions (XJ vehicles). • MOPAR ATF PLUS type 7176 (YJ vehicles).


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LUBRICATION AND MAINTENANCE

Fig. 4 Dipstick & ATF Level SPECIAL ADDITIVES The addition of any special-type fluid to a Jeep automatic transmission is not recommended. The only exception is the addition of black-light detection dye to aid in detecting the source of ATF leaks. The use of transmission sealing additives should also be avoided. Black-light detection dye is factory-installed in automatic transmissions and, unless the ATF has been drained and re-placed, it is not necessary to add dye.

FLUID AND FILTER CHANGE The automatic transmission fluid and filter should be changed at the intervals described in the Maintenance Schedules section of this Group. Refer to Group 21, Transmission for proper service procedures.

TRANSFER CASE (4WD VEHICLES) The transfer case should be inspected for fluid leaks and proper fluid level when other under vehicle service is performed.

FLUID LEVEL The transfer case fill hole plug is located at the rear of the housing (Fig. 5).

J (1) Raise and support the vehicle. (2) Remove the fill hole plug from the transfer case (Fig. 5). The fluid (ATF) level should be at the bottom edge of the fill hole. The level can be slightly below the bottom edge of the fill hole if the fluid is cold. (3) If the level is not acceptable, raise the fluid level to the bottom edge of the fill hole. (4) Install the fill hole plug (Fig. 5). Tighten the fill hole plug to 48 Nzm (35 ft-lbs) torque. (5) Remove the support and lower the vehicle.

FLUID DRAIN AND REFILL The Transfer Case should be serviced as specified in the Lubrication and Maintenance Schedules. (1) Raise and support the vehicle. (2) Remove the fill hole plug (Fig. 5) from the transfer case. (3) Place an appropriate container under the transfer case drain hole plug (Fig. 5). (4) Remove the drain hole plug and drain the ATF from the transfer case into the container. CAUTION: Do not over-tighten the drain and fill hole plugs. Over-tightening can strip the hole threads and/or crack the aluminum housing. (5) Install the drain hole plug in the transfer case. Tighten the drain hole plug to 27 Nzm (20 ft-lbs) torque. (6) Fill the transfer case to the bottom edge of the fill hole. (7) Install the fill hole plug in the transfer case Tighten the plug to 27 Nzm (20 ft-lbs) torque. (8) Remove the support and lower the vehicle.

FLUID SPECIFICATION If it is necessary to add fluid to a transfer case (or when the fluid is changed), use MOPAR ATF PLUS type 7176 or an equivalent Mercon/Dexron III ATF.

FRONT AND REAR AXLES The front and rear axles should be inspected for fluid leaks and proper fluid level when other under vehicle service is performed. Refer to the Lubrication and Maintenance Schedule service intervals.

Fig. 5 Transfer Case—Typical Determine the transfer case fluid (ATF) level according to the following procedure.

LUBRICANT SPECIFICATIONS For normal vehicle operation, use SAE 75W-90, API Quality Grade GL-5 gear lubricant in all Jeep front (4WD only) and rear axles. Vehicles equipped with a Trac-Lok rear axle also require a friction modifier additive included with the gear lubricant. When involved in trailer towing applications use SAE 80W-140, API Quality Grade GL-5 gear lubricant in the rear axle. XJ Vehicles equipped with a class III trailer hitch require SAE 75W140 synthetic gear lubricant in the rear axle.


LUBRICATION AND MAINTENANCE

J LUBRICANT LEVEL Determine the axle differential housing lubricant level according to the following procedure. (1) Raise and support the vehicle. (2) Remove the fill-hole plug (Fig. 6 and 7) from the axle differential housing cover. The gear lubricant should be 13 mm (1/2 inch) below the bottom edge of the fill hole.

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(2) Place a container under the axle differential housing. (3) Remove the axle differential housing cover bolts. Remove the housing cover. (4) Allow the axle gear lubricant to completely drain into the container. CAUTION: Do not flush a rear axle Trac-Lok differential. Trac-Lok differentials may be cleaned only by disassembling the unit and wiping the components with clean, lint-free cloth. (5) Flush the inside of the differential housing with a flushing oil. Do not use water, steam, kerosene or gasoline for flushing. (6) Remove any residual RTV sealant/gasket material from the differential housing and cover. Thoroughly clean the contact surfaces with mineral spirits and dry the surfaces completely. (7) Apply a bead of MOPAR RTV Sealant, or an equivalent sealant, around the bolt circle on the housing and on the cover (Fig. 8).

Fig. 6 Rear Axle—Typical

Fig. 7 Front Axle (4WD)—Typical (3) If not acceptable, raise the lubricant level to 13 mm (1/2 inch) below the bottom edge of the fill hole. Add lubricant in small amounts to raise the level. (4) Install the fill-hole plug in the differential housing cover. Tighten the plug with 34 N°m (25 ft. lbs.) torque. (5) Remove the support and lower the vehicle.

LUBRICANT CHANGE When it becomes necessary to change the axle lubricant in a Jeep front or rear axle, use the following procedure. (1) Raise and support the vehicle.

Fig. 8 RTV Sealant Application—Typical If differential housing cover is not installed within 20 minutes after applying sealant, the sealant must be removed and another bead applied. (8) Install the cover on the differential housing with the attaching bolts (Fig. 9). Tighten the cover bolts with 47 Nzm (35 ft. lbs.) torque. (9) Remove the fill-hole plug and add the replacement gear lubricant to the differential housing. Refer to Specifications above. (10) Install the fill-hole plug. Tighten the plug with 34 N°m (25 ft. lbs.) torque.


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LUBRICATION AND MAINTENANCE

J LUBRICANT SPECIFICATION Use Mopar, Multi-purpose Grease or any lubricate that is identified as NLGI GC-LB lubricant.

RUBBER AND PLASTIC HOSES/TUBING The condition of underbody rubber hose and plastic tubing should be inspected whenever underbody service is performed. Rubber hoses and plastic tubing should be replaced immediately if there is any evidence of failure.

Fig. 9 Differential Housing Cover Installed (11) Remove the support and lower the vehicle.

HOSE/TUBING INSPECTION (1) Inspect all hose and tubing fittings for looseness and corrosion. Inspect the rubber hoses for brittleness and cracks. Thoroughly inspect the hose ends (those that are slipped over nipple connectors) for splits (Fig. 10, 11, 12, 13, 14, 15 and 16).

DRIVE SHAFTS Lubricate at the intervals described in the Maintenance Schedule section of this Group. Refer to Group 16, Propeller Shafts for proper service procedures. CAUTION: It is very important that drive shafts be lubricated at periodic intervals and that the specified type of lubricant be used. Failure to properly lubricate could result in premature wear of drive shaft components.

Fig. 11 Front Axle Vent Hose—YJ Vehicles (2) Inspect the surface of hoses and tubing for heat and mechanical damage. Hose and tubing located close to an exhaust pipe should be given special attention. (3) Inspect the rubber hose routing to ensure that the hoses do not contact any heat source, moving component, etc., that would potentially cause heat or mechanical damage. (4) Inspect all the hose connections to ensure that they are secure and there is no fluid leakage. Actual dripping of hot fluid should be noted and the clamps tightened in an attempt to stop the leakage before replacing the hose.

Fig. 10 Front Axle Vent Hose (4WD)—XJ Vehicles


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Fig. 12 Front Axle Vacuum Shift Tubing

Fig. 15 Rear Axle Vent Hose—YJ Vehicles

Fig. 13 Transfer Case Vent Hose (4WD)—Typical

Fig. 16 Rear Axle Vent Hose At Wheelhouse—YJ Vehicles

Fig. 14 Rear Axle Vent Hose—XJ Vehicles


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CHASSIS AND BODY COMPONENTS INDEX page Body Components . . . . . . . . . . . . . . . Chassis Component and Wheel Bearing Lubricants . . . . . . . . . . . . . . . . . . . . Front Wheel Bearings . . . . . . . . . . . . . Headlamps . . . . . . . . . . . . . . . . . . . . . Manual Steering Gear . . . . . . . . . . . . .

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CHASSIS COMPONENT AND WHEEL BEARING LUBRICANTS The chassis component and wheel bearing lubricants that are recommended for Jeep vehicles are identified by the NLGI Certification Symbol (Fig. 1). The symbol contains a coded designation that identifies the usage and quality of the lubricant.

Fig. 2 Steering Components (XJ)—Typical Fig. 1 NLGI Lubricant Container Certification/ Identification Symbol The letter G designates wheel bearing lubricant. Letter L designates chassis lubricant. When the letters are combined the lubricant can be used for dual applications. The suffix letters C and B designate the level of the lubricant for the application. The letter C represents level available for wheel bearing lubricant (G) and the letter B represents level available for chassis lubricant (L).

STEERING LINKAGE The steering linkage (Fig. 2) should be lubricated and inspected at the intervals described in the Maintenance Schedules section of this Group. Refer to Group 2, Front Suspension and Axles for proper service procedures.

LUBRICANT SPECIFICATION Use Mopar, Multi-purpose Grease or NLGI GC-LB lubricant equivalent to lubricate the steering linkage. INSPECTION (1) Inspect the steering linkage. Examine the tie rods and the drag link for bending, and the ball studs for looseness and excessive wear.

(2) Replace, as necessary, all torn/ruptured ballstud seals and damaged/defective steering linkage components. CAUTION: Use care to prevent lubricant from contacting the brake rotors.

FRONT WHEEL BEARINGS Some 2WD XJ vehicles are equipped with serviceable front wheel bearings. XJ 4WD vehicles have semi-floating axle shafts and axle shaft bearings that are lubricated via differential lube oil.

RECOMMENDED MAINTENANCE—2WD XJ VEHICLES If equipped, the serviceable front wheel bearings should be lubricated (re-packed) at the same time as front brake pad/caliper service is conducted. LUBRICANT SPECIFICATION Wheel bearings should be lubricated with a lubricant that is identified as NLGI GC-LB lubricant. INSPECTION/LUBRICATION (1) Remove the wheel/tire and the disc brake caliper. Do not disconnect the caliper brake fluid


LUBRICATION AND MAINTENANCE

J hose unless the caliper must also be removed for maintenance.Support the caliper with a hanger to prevent brake fluid hose damage. (2) Remove the dust cap, the cotter pin, the nut retainer, the adjustment nut, and the thrust washer from the spindle (Fig. 3). Discard the cotter pin.

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(14) Tighten the spindle nut with 28 Nzm (21 ft. lbs.) torque while rotating the disc brake rotor to seat the bearings. (15) Loosen the spindle nut 1/2 turn. While rotating the disc brake rotor, tighten the spindle nut with 2 Nzm (19 in. lbs.) torque. (16) Install the nut retainer and a replacement cotter pin. (17) Clean the dust cap and apply wheel bearing lubricant to the inside surface. Do not fill the dust cap with lubricant. (18) Install the dust cap. (19) Install the disc brake caliper.

POWER STEERING SYSTEM

Fig. 3 2WD Front Wheel Bearings—XJ Vehicles (3) Remove the wheel outer bearing from the hub. (4) Remove the wheel hub/disc brake rotor from the spindle. (5) Remove the seal and the inner wheel bearing from the hub cavity. (6) After removal, inspect both front wheel bearing races for indications of pitting, brinelling and excessive heat. (7) Wipe the spindle clean and apply a small amount of chassis/wheel bearing lubricant (NLGI GC-LB lubricant) to prevent rust. Wipe the wheel hub cavity clean.

The power steering fluid level should be inspected when other under hood service is performed. For proper service procedures, refer to Group 19, Steering. Inspect the power steering system (Fig. 4, and 5) for the sources of fluid leaks, steering gear housing cracks and ensure that the steering gear is securely attached to the vehicle frame rail. Inspect the steering damper for leaks and loose connections.

CAUTION: Do not over-fill the wheel hub cavity with lubricant. Excessive lubricant can cause overheating and bearing damage. Also, excessive lubricant can be forced out of the wheel hub cavity and contaminate the brake rotor/pads. (8) Partially fill the wheel hub cavity with chassis/ wheel bearing lubricant (NLGI GC-LB lubricant). (9) Pack the wheel bearings with chassis/wheel bearing lubricant (NLGI GC-LB lubricant). Ensure that sufficient lubricant is forced between the bearing rollers. (10) Install the wheel inner bearing in the wheel hub and install a replacement seal. (11) Clean the disc brake rotor contact surfaces, if necessary. (12) Install the wheel hub/disc brake rotor on the spindle. (13) Install the wheel outer bearing, the thrust washer, and the spindle nut.

Fig. 4 Power Steering System—XJ Vehicles FLUID SPECIFICATION Use MOPAR Power Steering Fluid, or an equivalent product. POWER STEERING FLUID INSPECTION WARNING: ENGINE MUST NOT BE RUNNING WHEN INSPECTING POWER STEERING FLUID LEVEL, PERSONAL INJURY CAN RESULT.


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LUBRICATION AND MAINTENANCE

J CAUTION: Do not over fill power steering reservoir when adding fluid, seal damage and leakage can result.

MANUAL STEERING GEAR The manual steering gear should be inspected for damage at the same time as the engine oil is changed and the oil filter is replaced. Refer to Group 19, Steering for additional information and service procedures.

POWER BRAKE SYSTEM

Fig. 5 Power Steering System—YJ Vehicles FLUID LEVEL The fluid level indicator (dipstick) is attached to the reservoir cap (Fig. 6). The fluid level in the reservoir can be determined with the fluid either hot or cold.

RECOMMENDED MAINTENANCE The brake fluid level (Fig. 8) should be inspected when other underhood service is done. With discbrakes, the fluid level can be expected to fall as the brake pads wear. However, a low fluid level can also be caused by a leak, and repair will then be necessary. Refer to Group 5, Brakes for proper service procedures. In addition, the brake system should be operationally tested periodically to ensure that it is functioning normally. FLUID SPECIFICATION Jeep power brake systems require MOPAR HeavyDuty Brake Fluid, or an equivalent product identified as conforming to FMVSS No. 116, DOT-3 and SAE J-1703 specifications. Use brake fluid from properly sealed container when adding fluid to the reservoir. Never use reclaimed fluid or fluid that does not conform to the DOT/SAE Standards. CAUTION: Use of a brake fluid that has a lower initial boiling point then specified by FMVSS No. 116, DOT 3 and SAE J-1703 could result in sudden brake failure during hard, prolonged braking. Do not allow petroleum base fluids to contaminate the brake fluid. Seal damage will result.

BRAKE FLUID LEVEL

Fig. 6 Power Steering Fluid Reservoir Dipstick— Typical (1) Remove the cap from the reservoir. (2) Depending on fluid temperature, if the level is below the FULL HOT mark or the FULL COLD mark on the dipstick, add power steering fluid. (3) Install the cap on the reservoir.

STANDARD POWER BRAKE SYSTEM (1) Clean the cover and the sides of the brake fluid reservoir. (2) Detach the bail retainer from the reservoir cover and remove the cover from the reservoir. (3) The brake fluid level should be 6 mm (1/4 in) below the rim of each reservoir well for XJ and YJ Vehicles (Fig. 7 and 8). If not, add brake fluid as necessary. (4) Inspect the reservoir cover bail retainer for tension and the cover for proper fit. The cover should fit tight and have a good seal.


LUBRICATION AND MAINTENANCE

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Fig. 7 Reservoir Fluid Level—YJ (2.5L) (5) Inspect the reservoir rubber diaphragm seal for cracks, cuts and distortion. (6) Inspect the brake fluid tubing fittings and the master cylinder housing for indications of fluid leakage. Repair as necessary. (7) Install the brake fluid reservoir cover. ANTI-LOCK BRAKE SYSTEM—XJ VEHICLES The anti-lock brake system fluid reservoir for XJ Vehicles is located in the engine compartment at the left side of the dash panel. (1) Turn the ignition switch ON and allow the pump motor to operate until it automatically de-energizes. (2) Clean the cover before removing it. CAUTION: Over-filling could cause fluid overflow and possible reservoir damage when the pump motor energizes. (3) The brake fluid level should be no lower than the ADD indicator on the side of the reservoir (Fig. 8). If not, add brake fluid as necessary. Raise the fluid level to the FULL indicator only. Do not over-fill the reservoir.

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BRAKE SYSTEM INSPECTION A brake system inspection should be included with all brake service procedures, and also each time the vehicle is lubricated. (1) Inspect the brake pads and linings for excessive wear, cracks, charred surfaces and broken rivets. (2) Inspect brake pads and linings for contamination from brake fluid, and/or other fluids. (3) Replace the brake pads linings if they are worn to within 0.78 mm (1/32 in) of the rivet head. (4) Operate the rear brake self-adjuster lever and pivot. Test the operation of the self-adjuster screw for ease of movement. (5) Inspect the self-adjuster components for wear or damage. (6) Inspect the disc brake caliper dust boot for damage and indications of brake fluid leakage. Inspect the bushings and pins for corrosion, tears and a binding condition. (7) Pull the rear wheel cylinder dust boot back to expose the wheel cylinder housing. Inspect for fluid leaks. Inspect the pistons and cylinder bores. (8) Inspect the brake differential warning valve and housing for indications of leakage. BRAKE FLUID HOSES/TUBING The rubber brake fluid hoses should be inspected for: • Correct length • Severe surface cracking • Swelling • Pulling • Scuffing • Excessively worn areas If the hose has cracks or abrasions in the rubber cover, the hose should be replaced. (1) Inspect all the hoses for kinks, a distorted condition and fluid leakage. (2) Inspect the hose and tubing routing under the vehicle. Verify that no hose/tubing is rubbing against any exhaust or other underbody components. PARKING BRAKE (1) Engage the parking brake pedal and then release it. (2) Test it for smooth operation and vehicle-holding capability. (3) Inspect the parking brake cables. (4) With the parking brake released, the rear wheels should rotate without restriction. Adjust the parking brake cable tension, if necessary (Fig. 9 and 10). (5) Repair any parking brake malfunctions.

Fig. 8 Reservoir Fluid Level—YJ-XJ and Anti-Lock Brake System (4) Turn the ignition switch OFF.

BRAKE OPERATIONAL TEST (1) Drive the vehicle and test for proper brake action.


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LUBRICATION AND MAINTENANCE

J sure. Refer to the tire inflation pressure decal located on the inside of the glove box door, and also to Group 22, Tires And Wheels.

ROTATION Refer to Group 22, Tires And Wheels for the recommended method of tire/wheel rotation for a Jeep vehicle.

BODY COMPONENTS LUBRICATION REQUIREMENTS All Jeep operating mechanisms and linkages should be lubricated when necessary. The door weatherstrip seals should be lubricated to prolong their life as well as to improve door sealing.

Fig. 9 Park Brake Equalizer (XJ)—Typical LUBRICANT SPECIFICATIONS All applicable exterior and interior vehicle operating mechanisms should be: • Inspected • Cleaned • Pivot/sliding contact areas on the mechanisms should then be lubricated. Multi-purpose NLGI GC-LB MOPAR Multi-Mileage Lubricant or an equivalent, should be used to lubricate the mechanisms. The door weatherstrip seals should be lubricated with silicone lubricant spray. Refer to the Body Lubricant Specifications chart below for additional lubricant applications.

Fig. 10 Park Brake Equalizer (YJ)—Typical (2) Note any indication of drum/rotor overheating, wheel dragging or the vehicle pulling to one side when the brakes are applied. (3) Evaluate any performance complaints received from the owner/operator. (4) Repair the brake system as necessary. Refer to Group, 5 Brakes for additional information and service procedures.

TIRES RECOMMENDED MAINTENANCE The general condition of the tires and the inflation pressures should be inspected at the same time the engine oil is changed and the oil filter is replaced. In addition, the tires/wheels should be rotated at the intervals described in the Maintenance Schedules section of this group. INSPECTION Inspect the tires for excessive wear, damage, etc. Test the tires for the recommended inflation pres-

LUBRICATION All pivoting and sliding contact areas, should be lubricated periodically to ensure quiet, easy operation and to protect against wear and corrosion. Areas include: • Seat tracks. • Door hinges/latches/strikers. • Liftgate/tailgate/hood hinges (Fig. 11). (1) As required, lubricate the body components with the specified lubricants. (2) Apply silicone lubricant to a cloth and wipe it on door seals to avoid over-spray that can soil passenger clothing. (3) Before applying lubricant, the component should be wiped clean. After lubrication, any excess lubricant should be removed. (4) The door lock cylinders should be lubricated 2 times each year (preferably autumn and spring): • Spray a small amount of lock cylinder lubricant directly into the lock cylinder. • Apply a small amount to the key and insert it into the lock cylinder. • Rotate it to the locked position and then back to the unlocked position several times. • Remove the key. Wipe the lubricant from it with a clean cloth to avoid soiling of clothing.


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BODY LUBRICANT SPECIFICATIONS

HEADLAMPS MAINTENANCE SCHEDULE Every six months check the headlamp beams to ensure that the headlamp beams are correctly positioned. AIM ADJUSTMENT Refer to Group 8L, Lamps for headlamp aim adjustment procedures.

SPEEDOMETER CABLE

Fig. 11 Hood Hinge Lubrication—XJ Vehicles (5) Extra close attention should also be given to the hood latch components to ensure proper functioning.

SERVICE INFORMATION Speedometer cable lubrication is not necessary. For service information involving noisy cables, refer to Group 8E, Instrument Panel and Gauges.


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FRONT SUSPENSION AND AXLE CONTENTS page

AXLE NOISE/VIBRATION DIAGNOSIS . . . . . . . . 18 AXLE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . 49 FRONT WHEEL ALIGNMENT . . . . . . . . . . . . . . . . 5 GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1

page

MODEL 30 AXLE AND TUBE AXLE (2WD) . . . . TORQUE SPECIFICATIONS . . . . . . . . . . . . . . . . XJ FRONT SUSPENSION . . . . . . . . . . . . . . . . . . YJ FRONT SUSPENSION . . . . . . . . . . . . . . . . . .

22 49 11 15

GENERAL INFORMATION FRONT SUSPENSION XJ VEHICLES The XJ front suspension is a link/coil design. This suspension is use on Left Hand Drive (LHD) and Right Hand Drive (RHD) vehicles. It is comprised of (Fig. 1); • Drive axle (4WD), tube axle (2WD)

• • • • • •

Track bar Stabilizer bar Upper and lower suspension arms Coil springs Dual-action shock absorbers Jounce bumpers The link/coil suspension allows each wheel to adapt to different road surfaces without greatly affecting

Fig. 1 XJ Front Suspension (LHD)


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the opposite wheel. Wheels are attached to a hub/ bearings which bolts to the knuckles. The hub/bearing is not serviceable and is replaced as a unit. Steering knuckles pivot on replaceable ball studs attached to the axle tube yokes. The upper and lower suspension arms are different lengths, with bushings at both ends. They bolt the axle assembly to the body. The lower arms uses shims at the body mount to allow for adjustment of caster and drive shaft pinion angle. The suspension arm travel is limited through the use of jounce bumpers in compression and shocks absorbers in rebound. Suspension components which use rubber bushings should be tightened at vehicle ride height. This will prevent premature failure of the bushing and maintain ride comfort. Bushings must never be lubricated. The coil springs control ride quality and maintain proper ride height. The coil springs mount up in the fender shield which is part of the unitized body bracket. A rubber isolator is located between the top of the spring and the frame. The bottom of the spring seats on a axle pad and is retained with a clip. The shock absorbers dampen jounce and rebound of the vehicle over various road conditions. The top of the shock absorbers are bolted to the body. The bottom of the shocks are bolted to the axle spring bracket. The stabilizer bar is used to minimize vehicle body roll during turns. The spring steel bar helps to control the vehicle body in relationship to the suspension. The bar extends across the front underside of the chassis and connects to the body rails. Links are connected from the bar to the axle brackets. Stabilizer bar mounts are isolated by rubber bushings. The track bar is used to minimize front axle sideto-side movement. The bar is attached to a frame rail bracket with a ball stud and isolated with a bushing at the axle bracket.

TUBE AXLE (2WD VEHICLES) The front axle used on two-wheel drive vehicles is a one-piece, tubular axle (Fig. 2). The tubular axle mounts in the same bracketry as the four-wheel drive axle. The steering knuckles and hub bearing assemblies are the same as used on the Model 30 drive axle. YJ VEHICLES The Wrangler (YJ) front suspension is leaf spring design comprised of (Fig. 3); • Drive axle • Track bar • Stabilizer bar • Leaf springs • Dual-action shock absorbers • Jounce bumpers (used to limit the travel of the suspension)

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Fig. 2 Front Axle—2WD Vehicles

Fig. 3 YJ Front Suspension The front suspension has semi-elliptic multi-leaf springs mounted to the axle assembly. The rearward end of the springs are mounted to the frame rail hangers. The forward end of the springs are attached to the frame with shackles. The springs and shackles use rubber bushings to isolate road noise. The shackles allow the springs to change their length as the vehicle moves over various road conditions. The


J spring and axle travel (jounce or rebound) is limited through use of rubber bumpers mounted on the frame. Suspension components which use rubber bushings should be tightened at vehicle ride height. This will prevent premature failure of the bushing and maintain ride comfort. The bushings should never be lubricated. The shocks absorbers dampen jounce and rebound of the vehicle over various road conditions. The top of the shock absorbers bolt to the frame. The bottom of the shocks bolt to the axle brackets. The stabilizer bar is used to minimize vehicle front sway during turns. The spring steel bar helps control vehicle body in relationship to the suspension movement. The bar extends across the front underside of the chassis and connects to the frame rails. Links connect the bar to the axle brackets. Stabilizer bar mounts are isolated by rubber bushings. The track bar is used to minimize front axle sideto-side movement. The track bar is attached to a frame rail bracket and axle bracket. The bar uses bushings at both ends.

FRONT SUSPENSION AND AXLE

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Fig. 4 Model 30 Differential Cover

FRONT DRIVE AXLE It is not necessary to remove the complete axle from the vehicle for routine differential service. If the differential housing or axle shaft tubes are damaged, the complete axle assembly can be removed and serviced. For complete drive axle assembly removal and installation refer to Drive Axle Assembly Replacement in this Group. The removable cover provides for servicing without removing axle from vehicle. The integral type housing, hypoid gear design has the centerline of the pinion set above the centerline of the ring gear. The Model 30 axle has the assembly part number and gear ratio listed on a tag. The tag is attached to the housing cover (Fig. 4). Build date identification codes are stamped on the axle shaft tube cover side. XJ and YJ axles are equipped with an optional A.B.S. brake system. The A.B.S. tone rings are pressed onto the axle shaft near the hub and knuckle. For additional information on the A.B.S. system refer to Group 5, Brakes. • XJ vehicles use a non-disconnect axle. • YJ vehicles use a vacuum disconnect axle (Fig. 5).

STANDARD DIFFERENTIAL OPERATION The differential gear system divides the torque between the axle shafts. It allows the axle shafts to rotate at different speeds when turning corners. Each differential side gear is splined to an axle shaft. The pinion gears are mounted on a pinion mate shaft and are free to rotate on the shaft. The

Fig. 5 Disconnect Feature pinion gear is fitted in a bore in the differential case and is positioned at a right angle to the axle shafts. In operation, power flow occurs as follows: • Pinion gear rotates the ring gear • Ring gear (bolted to the differential case) rotates the case • Differential pinion gears (mounted on the pinion mate shaft in the case) rotate the side gears • Side gears (splined to the axle shafts) rotate the shafts During straight-ahead driving, the differential pinion gears do not rotate on the pinion mate shaft. This occurs because input torque applied to gears is divided and distributed equally between the two side gears. As a result, the pinion gears revolve with the pinion mate shaft but do not rotate around it (Fig. 6). When turning corners, the outside wheel must travel a greater distance than the inside wheel. This difference must be compensated for in order to prevent the wheels from scuffing and skidding through the turn. To accomplish this, the differential allows


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FRONT SUSPENSION AND AXLE

J tions. This allows the side gear and axle shaft attached to the outside wheel to rotate at a faster speed.

Fig. 6 Differential Operation—Straight-Ahead Driving the axle shafts to turn at unequal speeds (Fig. 7). In this instance, the input torque applied to the pinion gears is not divided equally. The pinion gears now rotate around the pinion mate shaft in opposite direc-

Fig. 7 Differential Operation—On Turns


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FRONT WHEEL ALIGNMENT INDEX page

page

Alignment Measurements and Adjustments . . . . . . . 8 General Information . . . . . . . . . . . . . . . . . . . . . . . . 5

Pre-Alignment Inspection

GENERAL INFORMATION

top of the knuckle forward provides negative caster. Caster is a directional stability angle. This angle enables the front wheels to return to a straight ahead position after turns (Fig. 1). • CAMBER is the inward or outward tilt of the wheel relative to the center of the vehicle. Tilting the top of the wheel inward provides negative camber. Tilting the top of the wheel outward provides positive camber. Incorrect camber will cause wear on the inside or outside edge of the tire (Fig. 1). The angle is not adjustable, the damaged component(s) must be replaced to correct mis-alignment. • WHEEL TOE POSITION is the difference between the leading inside edges and trailing inside edges of the front tires (Fig. 1). Incorrect wheel toe position is the most common cause of unstable steering and un-

Front wheel alignment involves the correct positioning of the wheels in relation to the vehicle. The positioning is accomplished through suspension and steering linkage adjustments. An alignment is considered essential for efficient steering, good directional stability and to maximize tire wear. The most important measurements of front end alignment are caster, camber and toe position. Routine inspection of the front suspension and steering components is a good preventative maintenance practice. Inspection also helps to ensure safe operation of the vehicle. • CASTER is the forward or rearward tilt of the steering knuckle from vertical. Tilting the top of the knuckle rearward provides positive caster. Tilting the

Fig. 1 Wheel Alignment Measurements

.................... 6


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FRONT SUSPENSION AND AXLE

even tire wear. The wheel toe position is the final front wheel alignment adjustment. • STEERING AXIS INCLINATION ANGLE is measured in degrees and is the angle that the steering knuckles are tilted (Fig. 1). The inclination angle has a fixed relationship with the camber angle. It will not change except when a spindle or ball stud is damaged or bent. The angle is not adjustable, the damaged component(s) must be replaced to correct misalignment. WARNING: DO NOT ATTEMPT TO MODIFY ANY SUSPENSION OR STEERING COMPONENT BY HEATING AND BENDING.

PRE-ALIGNMENT INSPECTION Before starting a front wheel alignment, the following inspection and necessary corrections must be completed.

J (1) Tires with the same recommended air pressure, size, and thread wear. Refer to Group 22, Tires And Wheels for diagnosis information. (2) Front wheel bearings for wear and looseness. (3) Ball studs, steering linkage pivot points and steering gear for looseness, roughness, binding or wear. Refer to Group 19, Steering for additional information. (4) Front wheels for excessive radial or lateral runout and unbalance. Refer to Group 22, Tires And Wheels for diagnosis information. (5) Suspension components for wear. Check components for correct torque. Refer to Groups 2 and 3, Suspension and Axle for additional information.


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FRONT SUSPENSION AND AXLE SUSPENSION AND STEERING SYSTEM DIAGNOSIS

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FRONT SUSPENSION AND AXLE

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Fig. 2 Adjustment—YJ Vehicles

ALIGNMENT MEASUREMENTS AND ADJUSTMENTS Before each alignment reading, the vehicle should be jounced (rear first, then front). Grasp each bumper at the center and jounce the vehicle up and down several times. Always release the bumper in the down position. Set the front end alignment to specifications with the vehicle at its NORMALLY RIDE HEIGHT.

CAMBER The wheel camber angle is preset. This angle is not adjustable and cannot be altered. CASTER Before checking the caster of the front axle for correct angle, be sure the axle is not bent or twisted. Road test the vehicle, make left and right turns. If the steering wheel returns to the center position unassisted, the caster angle is correct. If steering wheel

Fig. 3 Adjustment—XJ Vehicles does not return toward the center position unassisted, an incorrect caster angle is probable. Caster can be adjusted by installing the appropriate size shims (Fig. 2, 3). Changing caster angle will also change the front propeller shaft angle. The propeller shaft angle has priority over caster. Refer to Group 16, Propeller Shafts for additional information.

TOE POSITION—XJ VEHICLES The wheel toe position adjustment should be the final adjustment. (1) Start the engine if equipped with power steering. Turn wheels both ways before straightening the

Fig. 4 Steering Linkage—XJ (LHD)


FRONT SUSPENSION AND AXLE

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Fig. 5 Steering Linkage—XJ (RHD) wheels. Secure the steering wheel with the front wheels in the straight-ahead position. Turn off the engine. (2) Loosen the adjustment sleeve clamp bolts (Fig. 4, 5). (3) Adjust the right wheel toe position with the drag link. Turn the sleeve until the right wheel is at specifications. Position the clamp bolts as shown (Fig. 6) and tighten to 49 Nzm (36 ft. lbs.) torque. Make sure the toe setting does not change during clamp tightening.

Fig. 6 Drag Link and Tie Rod Clamp Location (LHD)

(4) Adjust the left wheel toe position with the tie rod. Turn the sleeve until the left wheel is at specifications. Position the clamp bolts as shown (Fig. 6) and tighten to 27 Nzm (20 ft. lbs.) torque. Make sure the toe setting does not change during clamp tightening. (5) Verify the right toe setting.


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FRONT SUSPENSION AND AXLE

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Fig. 7 Steering Linkage YJ Vehicles TOE POSITION—YJ VEHICLES The wheel toe position should be the final front wheel alignment adjustment. In all instances follow the equipment manufacturer’s recommended procedure. (1) Start the engine if equipped with power steering. Turn wheels both ways before straightening the wheels. Secure the steering wheel with the front wheels in the straight-ahead position. Turn off the engine. (2) Loosen the adjustment sleeve clamp bolts on the tie rod (Fig. 7).

The tie rod and adjustment sleeve have both right and left hand threads to provide equal adjustment for each wheel. (3) After the adjustment is completed, position the tie rod adjustment sleeve clamp bolts as shown. (4) Tighten the adjustment sleeve clamp bolts to 27 Nzm (20 ft. lbs.) torque. (5) Complete the adjustment. Position the drag link clamp bolts as shown. Tighten the bolts to 49 Nzm (36 ft. lbs.) torque.

ALIGNMENT SPECIFICATIONS—XJ VEHICLES

ALIGNMENT SPECIFICATIONS—YJ VEHICLES


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XJ FRONT SUSPENSION

INDEX page Axle Bushing Replacement . . . . . . . . . . . . . . . . . . Coil Spring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lower Suspension Arm . . . . . . . . . . . . . . . . . . . . . Service Information . . . . . . . . . . . . . . . . . . . . . . . . Shock Absorber . . . . . . . . . . . . . . . . . . . . . . . . . .

12 14 13 11 13

page Spring and Shock Diagnosis . . . . . . . . . . . . . . . . . Stabilizer Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . Track Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Upper Suspension Arm . . . . . . . . . . . . . . . . . . . . .

13 11 11 12

SERVICE INFORMATION Periodic lubrication of the steering system and suspension components is required. Refer to Group 0, Lubrication And Maintenance for the service interval. CAUTION: Suspension components with rubber bushings should be tightened with the vehicle at normal height. It is important to have the springs supporting the weight of the vehicle when the fasteners are torqued. If springs are not at their normal ride position, vehicle ride comfort could be affected and premature bushing wear may occur. Rubber bushings must never be lubricated.

TRACK BAR REMOVAL (1) Raise and support the vehicle. (2) Remove the cotter pin and nut from the ball stud end at the frame rail bracket (Fig. 1). A puller tool may be necessary to separate the ball stud from the frame rail bracket. (3) Remove the bolt and flag nut from the axle shaft tube bracket (Fig. 1). Remove the track bar. INSTALLATION (1) Install the track bar at axle tube bracket. Loosely install the retaining bolt and flag nut (Fig. 1). (2) It may be necessary to pry the axle assembly over to install the track bar at the frame rail. Install track bar at the frame rail bracket. Install the retaining nut on the stud (Fig. 1). (3) Remove the supports and lower the vehicle. (4) Tighten the retaining bolt at the axle shaft tube bracket to 100 Nzm (74 ft. lbs.) torque. (5) Tighten the ball stud nut to 81 Nzm (60 ft. lbs.) torque. Install a new cotter pin.

Fig. 1 Track Bar (LHD)

STABILIZER BAR REMOVAL (1) Raise and support the vehicle. (2) Disconnect the stabilizer bar links from the axle brackets (Fig. 2). (3) Disconnect the stabilizer bar from the links. (4) Disconnect the stabilizer bar clamps from the frame rails. Remove the stabilizer bar. INSTALLATION (1) Inspect stabilizer bar bushings ( Fig. 2). Replace bushings if cracked, cut, distorted, or worn. (2) Position the stabilizer bar on the frame rail and install the bushings and clamps. Ensure the bar is centered with equal spacing on both sides. Tighten the bolts to 75 Nzm (40 ft. lbs.). (3) Install the links and grommets onto the stabilizer bar and axle brackets (Fig. 2). Tighten the nut at the connecting links at the axle bracket to 95 Nzm (70 ft. lbs.) torque.


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FRONT SUSPENSION AND AXLE

Fig. 2 Stabilizer Bar

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Fig. 3 Upper and Lower Suspension Arms

(3) Tighten the stabilizer bar to connecting link nut to 36 Nzm (27 ft. lbs.) torque. (4) Remove the supports and lower the vehicle.

UPPER SUSPENSION ARM REMOVAL (1) Raise and support the vehicle. (2) Remove the upper suspension arm nut and bolt at the axle bracket (Fig. 3). (3) Remove the nut and bolt (Fig. 3) at the frame rail and remove the upper suspension arm. INSTALLATION (1) Position the upper suspension arm at the axle and frame rail (Fig. 3). (2) Install the bolts and finger tighten the nuts (Fig. 3). (3) Remove the supports and lower the vehicle. (4) Tighten the nut at the axle to 75 Nzm (55 ft. lbs.) torque. Tighten the nut at the frame bracket to 90 Nzm (66 ft. lbs.) torque.

AXLE BUSHING REPLACEMENT (1) Remove the upper suspension arm from axle. Refer to Upper Suspension Arm Removal in this Group. (2) Insert Spacer 7932-3 (J-35581-3) around the bushing in the axle bracket ears (Fig. 4). (3) Assemble and install Bushing Removal/Installer (Fig. 4). (4) Remove the bushing by tightening the hex-head on Long Nut.

Fig. 4 Axle Bracket Bushing Removal For two-wheel drive axles and right side on Model 30 axle, do not remove Spacer 7932-3 (J35581-3) at this time. (5) Position the new bushing on Installer. (6) Install the bushing by tightening the hex-head on Long Nut (Fig. 5). Remove Spacer 7932-3 (J35581-3). (7) Install the upper suspension arm to axle. Refer to Upper Suspension Arm Installation in this Group.


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INSTALLATION (1) Position the lower suspension arm at the axle bracket and rear bracket (Fig. 3). (2) Install the bolts and finger tighten the nuts (Fig. 3). (3) Remove support and lower the vehicle. (4) Tighten the front and rear nuts to 115 Nzm (85 ft. lbs.) torque.

SPRING AND SHOCK DIAGNOSIS

Fig. 5 Axle Bracket Bushing Installation

LOWER SUSPENSION ARM REMOVAL (1) Raise and support the vehicle. (2) Remove the lower suspension arm nut and bolt from the axle bracket (Fig. 3). (3) Remove the nut and bolt (Fig. 3) from the rear bracket and remove the lower suspension arm.

A squeak noise from the shock absorber can be produced if movement between the rubber bushings and the metal occurs. This noise can usually be stopped by tightening the attaching nuts. If the squeak noise persists, inspect for damaged and worn bushings, and attaching components. Repair as necessary. The shock absorber bushings do not require any type of lubrication. Do not lubricate the bushings to reduce bushing noise. Grease or mineral oil-base lubricants will deteriorate the bushing rubber. The shock absorbers are not refillable or adjustable. If a malfunction occurs, the shock absorber must be replaced. To test a shock absorber, hold it in an upright position and force the piston into and out of the cylinder four or five times. The action throughout each stroke should be smooth and even.

SHOCK ABSORBER REMOVAL (1) Remove the nut, retainer and grommet from the upper stud in the engine compartment (Fig. 6). (2) Remove the lower nuts and bolts from the axle bracket (Fig. 6). Remove the shock absorber.

Fig. 6 Coil Spring & Shock Absorber


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FRONT SUSPENSION AND AXLE

INSTALLATION (1) Position the lower retainer and grommet on the upper stud. Insert the shock absorber through the shock tower hole. (2) Install the lower bolts and nuts. Tighten nuts to 23 Nzm (17 ft. lbs.) torque. (3) Install the upper grommet and retainer on the stud in the engine compartment. Install the nut and tighten to 10 Nzm (8 ft. lbs.) torque.

COIL SPRING REMOVAL (1) Raise and support the vehicle. Position a hydraulic jack under the axle to support it. (2) Remove the wheel if necessary. (3) Mark and disconnect the front propeller shaft from the axle. (4) Disconnect the lower suspension arms from the axle (Fig. 6). (5) Disconnect the stabilizer bar link and shock absorber from the axle. (6) Disconnect the track bar from the frame rail bracket.

J (7) Disconnect the drag link from the pitman arm. (8) Lower the axle until the spring is free from the upper mount. Remove the coil spring clip (Fig. 6) and remove the spring. (9) Pull jounce bumper out of mount.

INSTALLATION (1) Install jounce bumper into mount. (2) Position the coil spring on the axle pad. Install the spring clip and bolt (Fig. 6). Tighten bolt to 21 Nzm (16 ft. lbs.) torque. (3) Raise the axle into position until the spring seats in the upper mount. (4) Connect the stabilizer bar links and shock absorbers to the axle bracket. Connect the track bar to the frame rail bracket. (5) Install the lower suspension arms to the axle. DO NOT TIGHTEN AT THIS TIME. (6) Install the front propeller shaft to the axle. (7) Remove the supports and lower the vehicle. (8) Tighten lower suspension arms nuts to 115 Nzm (85 ft. lbs.) torque.


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YJ FRONT SUSPENSION INDEX page Leaf Spring . . . . . . . . . . . . . . . . . . . . Leaf Spring Eye Bushing Replacement Service Information . . . . . . . . . . . . . . Shock Absorber . . . . . . . . . . . . . . . .

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16 17 15 16

page Spring and Shock Diagnosis . . . . . . . . . . . . . . . . . 15 Stabilizer Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Track Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

SERVICE INFORMATION Periodic lubrication of the steering system and suspension components is required. Refer to Group 0, Lubrication And Maintenance for the service interval. CAUTION: Suspension components with rubber bushings should be tightened with the vehicle at normal height. It is important to have the springs supporting the weight of the vehicle when the fasteners are torqued. If springs are not at their normal ride position, vehicle ride comfort could be affected and premature bushing wear may occur. Rubber bushings must never be lubricated.

TRACK BAR REMOVAL (1) Raise and support the vehicle. (2) Remove the retaining nuts and bolts (Fig. 1) from the axle bracket and frame bracket. Remove track bar. INSTALLATION (1) Position track bar at axle shaft tube bracket. Loosely install the retaining bolt and nut (Fig. 1). (2) Loosely install the retaining bolt and nut at the frame bracket. (3) Remove support and lower vehicle. (4) Tighten the retaining nut at the axle shaft tube bracket to 100 Nzm (74 ft. lbs.) torque. (5) Tighten the retaining nut at the frame bracket to 142 Nzm (105 ft. lbs.) torque.

STABILIZER BAR REMOVAL (1) Raise and support the vehicle. (2) Remove the retaining nut from the connecting link bolt (Fig. 2). (3) Remove the retaining clamps from frame rails (4) Remove the stabilizer bar. INSTALLATION (1) Inspect the stabilizer bar bushings (Fig. 2). Replace the bushings if cracked, cut, distorted, or worn.

Fig. 1 Track Bar (2) Position the stabilizer bar on the frame. Install the retaining brackets and fasteners. Tighten bolts to 41 Nzm (30 ft. lbs.) torque. (3) Install the link upper bolts and nuts. Tighten the nuts to 61 Nzm (45 ft. lbs.) torque. (4) Tighten the link spring bracket nuts to 61 Nzm (45 ft. lbs.) torque. (5) Lower the vehicle.

SPRING AND SHOCK DIAGNOSIS A squeak noise from the shock absorber or springs can be produced if movement between the rubber bushings and the metal occurs. This noise can usually be stopped by tightening the attaching nuts. If the squeak noise persists, inspect for damaged and worn bushings, and attaching components. Repair as necessary if any of these conditions exist.


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FRONT SUSPENSION AND AXLE

Fig. 2 Stabilizer Bar The shock absorber bushings do not require any type of lubrication. Do not lubricate the bushings to reduce bushing noise. Grease or mineral oil-base lubricants will deteriorate the bushing rubber. The shock absorbers are not refillable or adjustable. If a malfunction occurs, the shock absorber must be replaced. To test a shock absorber, hold it in an upright position and force the piston into and out of the cylinder four or five times. The action throughout each stroke should be smooth and even.

SHOCK ABSORBER REMOVAL (1) Remove the nut, retainer and grommet from the upper stud on the frame bracket (Fig. 3). (2) Raise and support the vehicle. (3) Remove the nut, washers and bolt from the shock absorber lower eye (Fig.3). (4) Remove the shock absorber. (5) Remove the remaining grommet and retainer from the shock absorber stud. INSTALLATION (1) Position the lower retainer and grommet on the upper stud. Insert the shock absorber through the shock tower hole. (2) Install the lower bolts and nuts. Tighten the nuts to 61 Nzm (45 ft. lbs.) torque. (3) Install the upper grommet and retainer on the stud on the frame bracket. Install the nut and tighten to 12 Nzm (9 ft. lbs.) torque.

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Fig. 3 Spring & Shock Absorber

LEAF SPRING REMOVAL (1) Raise the vehicle. (2) Support the vehicle with jack stands placed under the frame. (3) Position a hydraulic jack under the axle. Raise the axle to relieve the axle weight from the springs. (4) Remove the stabilizer bar links attaching nut. (5) Remove the nuts, the U-bolts and spring bracket from the axle. (6) Remove the nut and bolt that attaches the spring front eye to the shackle (Fig. 3). (7) Remove the nut and bolt from the spring rear eye. (8) Remove the spring from the vehicle. The spring can be disassembled by removing the spring clips and the center bolt. If the spring bushings require replacement, refer to the bushing removal and installation procedures. INSTALLATION (1) Position the spring front eye in the shackle. Loosely install the attaching bolt and nut. Do not tighten at this time. (2) Position the rear eye in the hanger bracket. Loosely install the attaching bolt and nut (Fig. 3). Do not tighten at this time. (3) Position the axle. Install the spring bracket, U-bolts and nuts (Fig. 3). Tighten the U-bolt nuts to 122 Nzm (90 ft. lbs.) torque. (4) Attach the stabilizer bar links. (5) Remove the hydraulic jack.


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FRONT SUSPENSION AND AXLE

(6) Remove the support stands and lower the vehicle. (7) Tighten the front shackle plate nut (Fig. 3) to 135 Nzm (100 ft. lbs.) torque. (8) Tighten the rear eye bracket nut to 142 Nzm (105 ft. lbs.) torque.

LEAF SPRING EYE BUSHING REPLACEMENT (1) Assemble tools shown (Fig. 4). Tighten the nut located at the socket wrench end of the threaded rod until the bushing is forced out. (2) Assemble and align the bushing installation tools. (3) Align the bushing with the spring eye and tighten the nut located at the socket wrench end of the threaded rod. Tighten until the bushing is forced into the spring eye. The bushing must be centered in the spring eye. The ends of the bushing must be flush or slightly recessed within the end surfaces of the spring eye.

Fig. 4 Spring Eye Bushing Removal

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AXLE NOISE/VIBRATION DIAGNOSIS INDEX page

page

Driveline Snap . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Gear and Bearing Noise . . . . . . . . . . . . . . . . . . . . 18 General Information . . . . . . . . . . . . . . . . . . . . . . . 18

Low Speed Knock . . . . . . . . . . . . . . . . . . . . . . . . . 19 Vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

GENERAL INFORMATION

GEAR AND BEARING NOISE

Axle bearing problem conditions are usually caused by: • Insufficient or incorrect lubricant • Foreign matter/water contamination • Incorrect bearing preload torque adjustment • Incorrect backlash (to tight) When serviced, the bearings must be cleaned thoroughly. They should be dried with lint-free shop towels. Never dry bearings with compressed air. This will overheat them and brinell the bearing surfaces. This will result in noisy operation after repair. Axle gear problem conditions are usually the result of: • Insufficient lubrication • Incorrect or contaminated lubricant • Overloading (excessive engine torque) or exceeding vehicle weight capacity • Incorrect clearance or backlash adjustment Insufficient lubrication is usually the result of a housing cover leak. It can also be from worn axle shaft or pinion gear seals. Check for cracks or porous areas in the housing or tubes. Using the wrong lubricant will cause overheating and gear failure. Gear tooth cracking and bearing spalling are indicators of this. Axle component breakage is most often the result of: • Severe overloading • Insufficient lubricant • Incorrect lubricant • Improperly tightened components Overloading occurs when towing heavier than recommended loads. Component breakage can occur when the wheels are spun excessively. Incorrect lubricant quantity contributes to breakage. Loose differential components can also cause breakage. Incorrect bearing preload or gear backlash will not result in component breakage. Mis-adjustment will produce enough noise to cause service repair before a failure occurs. If a mis-adjustment condition is not corrected, component failure can result. Excessive bearing preload may not be noisy. This condition will cause high temperature which can result in bearing failure.

GEAR NOISE Axle gear noise can be caused by insufficient lubricant. Incorrect backlash, tooth contact, or worn/damaged gears can cause noise. Gear noise usually happens at a specific speed range. The range is 30 to 40 mph, or above 50 mph. The noise can also occur during a specific type of driving condition. These conditions are acceleration, deceleration, coast, or constant load. When road testing, accelerate the vehicle to the speed range where the noise is the greatest. Shift out-of-gear and coast through the peak-noise range. If the noise stops or changes greatly, check for insufficient lubricant. Incorrect ring gear backlash, or gear damage can cause noise changes. Differential side and pinion gears can be checked by turning the vehicle. They usually do not cause noise in straight-ahead driving. These gears are loaded during vehicle turns. If noise does occur during vehicle turns, the side or pinion gears could be worn or damaged. A worn pinion gear mate shaft can also cause a snapping or a knocking noise. BEARING NOISE The axle shaft, differential and pinion gear bearings can all produce noise when worn or damaged. Bearing noise can be either a whining, or a growling sound. Pinion gear bearings have a constant-pitch noise. This noise changes only with vehicle speed. Pinion bearing noise will be higher because it rotates at a faster rate. Drive the vehicle and load the differential. If bearing noise occurs the pinion rear bearing is the source of the noise. If the bearing noise is heard during a coast, front bearing is the source. Worn, damaged differential bearings usually produce a low pitch noise. Differential bearing noise is similar to pinion bearing. The pitch of differential bearing noise is also constant and varies only with vehicle speed.


J Axle shaft bearings produce noise and vibration when worn or damaged. The noise generally changes when the bearings are loaded. Road test the vehicle. Turn the vehicle sharply to the left and to the right. This will load the bearings and change the noise level. Where axle bearing damage is slight, the noise is usually not noticeable at speeds above 30 mph.

LOW SPEED KNOCK Low speed knock is generally caused by a worn Ujoint or by worn side-gear thrust washers. A worn pinion gear shaft bore will also cause low speed knock.

VIBRATION Vibration at the rear of the vehicle is usually caused by a: • Damaged drive shaft • Missing drive shaft balance weight • Worn, out-of-balance wheels • Loose wheel lug nuts • Worn U-joint • Loose spring U-bolts • Loose/broken springs • Damaged axle shaft bearings • Loose pinion gear nut • Excessive pinion yoke run out

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• Bent axle shaft Check for loose or damaged front-end components or engine/transmission mounts. These components can contribute to what appears to be a rear-end vibration. Do not overlook engine accessories, brackets and drive belts. All driveline components should be examined before starting any repair. Refer to Group 22—Tires And Wheels for additional information involving vibration diagnosis.

DRIVELINE SNAP A snap or clunk noise when the vehicle is shifted into gear (or the clutch engaged), can be caused by: • High engine idle speed • Loose engine/transmission/transfer case mounts • Worn U-joints • Loose spring mounts • Loose pinion gear nut and yoke • Excessive ring gear backlash • Excessive differential side gear-to-case clearance The source of a snap or a clunk noise can be determined with the assistance of a helper. Raise the vehicle on a hoist with the wheels free to rotate. Instruct the helper to shift the transmission into gear. Listen for the noise, a mechanics stethoscope is helpful in isolating the source of a noise.


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FRONT SUSPENSION AND AXLE SERVICE DIAGNOSIS

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FRONT SUSPENSION AND AXLE SERVICE DIAGNOSIS (CONT’D)

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MODEL 30 AXLE AND TUBE AXLE (2WD) INDEX page Axle Bushing Replacement . . . . . . . . . . . . . . . Axle Shaft—Cardan U-Joint . . . . . . . . . . . . . . . Backlash and Contact Pattern Analysis . . . . . . Cleaning/Inspection . . . . . . . . . . . . . . . . . . . . . Differential and Pinion Measurement . . . . . . . . Differential Assembly . . . . . . . . . . . . . . . . . . . . Differential Disassembly . . . . . . . . . . . . . . . . . Differential Installation . . . . . . . . . . . . . . . . . . . Differential Removal . . . . . . . . . . . . . . . . . . . . Differential Shim Pack Measurement and Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . Drive Axle Assembly Replacement—XJ Vehicles Drive Axle Assembly Replacement—YJ Vehicles

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34 26 45 37 40 38 35 44 34

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INFORMATION The Model 30 front axles consists of a cast iron differential housing with axle shaft tubes extending from either side. The tubes are pressed into the differential housing and welded. The integral type housing, hypoid gear design has the centerline of the pinion set above the centerline of the ring gear. The axle has a fitting for a vent hose used to relieve internal pressure caused by lubricant vaporization and internal expansion. The axles are equipped with semi-floating axle shafts, meaning that loads are supported by the hub bearings. The axle shafts are retained by nuts at the hub bearings. The hub bearings are bolted to the steering knuckle at the outboard end of the axle tube yoke. The hub bearings are serviced as an assembly. The axles are equipped with ABS brake sensors. The sensors are attached to the knuckle assemblies and tone rings are pressed on the axle shaft. Use care when removing axle shafts as NOT to damage the tone wheel or the sensor. The stamped steel cover provides a means for inspection and servicing the differential. The Model 30 axle has the assembly part number and gear ratio listed on a tag. The tag is attached to the housing cover. Build date identification codes are stamped on the axle shaft tube cover side. The differential case is a one-piece design. The differential pinion mate shaft is retained with a roll pin. Differential bearing preload and ring gear backlash is adjusted by the use of shims (select thickness). The shims are located between the differential bearing cones and case. Pinion bearing preload is set and maintained by the use of collapsible spacer.

page Final Assembly . . . . . . . . . . . . . . . . . Hub Bearing and Axle Shaft . . . . . . . Information . . . . . . . . . . . . . . . . . . . . Inner Axle Shaft Oil Seal Replacement Lubricant Change . . . . . . . . . . . . . . . Lubricant Specifications . . . . . . . . . . . Pinion Gear Assembly/Installation . . . Pinion Gear Depth Information . . . . . Pinion Removal/Disassembly . . . . . . . Pinion Seal Replacement . . . . . . . . . Steering Knuckle and Ball Studs . . . . Vacuum Disconnect Axle—YJ Vehicles

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46 25 22 35 23 22 42 39 36 25 32 27

COMMAND-TRAC—YJ VEHICLES The Command-Trac system is a vacuum disconnect axle. The system has a two-piece axle shaft coupled together by a shift collar. For two-wheel drive operation, the vacuum motor and shift fork disengages the axle shaft splines. For four-wheel drive operation, the vacuum motor and shift fork engages the axle splines. SELEC-TRAC—XJ VEHICLES The Selec-Trac system is a non-disconnect axle. Shifting from two-wheel to four-wheel drive is done at the transfer case. For XJ vehicles equipped with Selec-Trac and ABS brake system, refer to Group 5—Brakes for additional service information.

LUBRICANT SPECIFICATIONS Multi-purpose, hypoid gear lubricant should be used for Model 30 axles. The lubricant should have MIL-L-2105C and API GL 5 quality specifications. MOPARt Hypoid Gear Lubricant conforms to both of these specifications. • The factory fill for the Model 30 axle is SAE Thermally Stable 80W-90 gear lubricant. Do not use heavier weight lubricant, this will cause axle engagement difficulties. • The factory installed lubricant quantity for the NON-DISCONNECT TYPE AXLE is 1.48 L (3.13 pts.). • The factory installed lubricant quantity for the VACUUM-DISCONNECT TYPE AXLE is 1.65 L (3.76 pts.). Refer to Group 0, Lubrication and Maintenance for additional information regarding temperature range, viscosity and fluid level.


FRONT SUSPENSION AND AXLE

J CAUTION: If axle is submerged in water, lubricant must be replaced immediately to avoid possible premature axle failure.

LUBRICANT CHANGE The gear lubricant will drain quicker if the vehicle has been recently driven. (1) Raise and support the vehicle. (2) Remove the lubricant fill hole plug from the differential housing cover. (3) Remove the differential housing cover and drain the lubricant from the housing. (4) Clean the housing cavity with a flushing oil, light engine oil or lint free cloth. Do not use water, steam, kerosene or gasoline for cleaning. (5) Remove the sealant from the housing and cover surfaces. Use solvent to clean the mating surfaces. (6) Apply a bead of MOPARt Silicone Rubber Sealant to the housing cover (Fig. 1). Allow the sealant to cure for a few minutes.

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DRIVE AXLE ASSEMBLY REPLACEMENT—XJ VEHICLES REMOVAL (1) Raise the vehicle and position support stands under the frame rails behind the lower suspension arm frame brackets. (2) Remove the front wheels. (3) Remove the brake components and ABS brake sensor (if equipped). Refer to Group 5—Brakes. (4) On 4WD vehicles, disconnect the axle vent hose. (5) On 4WD vehicles, mark the drive shaft yoke and axle pinion yoke for alignment reference. Disconnect the drive shaft from the axle. (6) Disconnect the stabilizer bar link at the axle bracket. (7) Disconnect the shock absorbers from axle bracket. (8) Disconnect the track bar from the axle bracket. (9) Disconnect the tie rod and drag link from the steering knuckle. Disconnect the steering damper from the axle bracket. (10) Support the axle with a hydraulic jack under the differential. (11) Disconnect the upper and lower suspension arms from the axle bracket. (12) Lower the jack enough to remove the axle. The coil springs will drop with the axle. (13) Remove the coil springs from the axle bracket. INSTALLATION CAUTION: Suspension components with rubber bushings should be tightened with the vehicle at normal height. It is important to have the springs supporting the weight of the vehicle when the fasteners are torqued. If springs are not at their normal ride position, vehicle ride comfort could be affected and premature bushing wear may occur. Rubber bushings must never be lubricated.

Fig. 1 Typical Housing Cover With Sealant Install the housing cover within 5 minutes after applying the sealant. If not installed the sealant must be removed and another bead applied. (7) Install the cover and any identification tag. Tighten the cover bolts in a criss-cross pattern to 41 Nzm (30 ft. lbs.) torque. (8) Refill the differential with MOPARt Hypoid Gear Lubricant to bottom of the fill plug hole. (9) Install the fill hole plug and lower the vehicle.

(1) Install the springs and retainer clip. Tighten the retainer bolts to 21 Nzm (16 ft. lbs.) torque. (2) Support the axle on a hydraulic jack under the differential. Position the axle under the vehicle. (3) Raise the axle with a floor jack and align it with the spring pads. (4) Position the upper and lower suspension arm at the axle bracket. Install bolts and nuts finger tighten. (5) Connect the track bar to the axle bracket and install the bolt. Do not tighten at this time. It is important that the springs support the weight of the vehicle when the track bar is connected. If springs are not at their usual position, vehicle ride comfort could be affected.


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FRONT SUSPENSION AND AXLE

(6) Install the shock absorber and tighten the bolt to 23 Nzm (17 ft. lbs.) torque. (7) Install the stabilizer bar link to the axle bracket. Tighten the nut to 95 Nzm (70 ft. lbs.) torque. (8) Install the drag link and tie rod to the steering knuckles and tighten the nuts to 47 Nzm (35 ft. lbs.) torque. Install the steering damper to the axle bracket and tighten the nut to 75 Nzm (55 ft. lbs.) torque. (9) Install the brake components and ABS brake sensor (if equipped). Refer to Group 5—Brakes. (10) On 4WD vehicles, connect the vent hose to the tube fitting. (11) On 4WD vehicles, align the reference marks and connect the drive shaft to the axle yoke. Tighten the U-joint clamp bolts to 19 Nzm (14 ft. lbs.) torque. (12) Check differential lubricant and add if necessary. (13) Install the wheel and tire assemblies. (14) Remove the supports and lower the vehicle. (15) Tighten the upper suspension arm nuts to 75 Nzm (55 ft. lbs.) torque. Tighten the lower suspension arm nuts to 115 Nzm (85 ft. lbs.) torque. (16) Tighten the track bar bolt at the axle bracket to 100 Nzm (74 ft. lbs.) torque. (17) Check the front wheel alignment.

DRIVE AXLE ASSEMBLY REPLACEMENT—YJ VEHICLES REMOVAL (1) Raise the vehicle and position support stands under the frame rails behind the spring frame brackets. (2) Remove the front wheels. (3) Remove the brake components and ABS brake sensor (if equipped). Refer to Group 5—Brakes. (4) Disconnect the axle vent hose and axle shift motor vacuum harness. (5) Mark the drive shaft yoke and axle pinion yoke for alignment reference. Disconnect the drive shaft from the axle. (6) Disconnect the stabilizer bar link at the axle bracket. (7) Disconnect the shock absorbers from axle bracket. (8) Disconnect the track bar from the axle bracket. (9) Disconnect the tie rod from the steering knuckle. Disconnect the steering damper from the axle bracket. (10) Support the axle with a hydraulic jack under the differential. Raise the axle just enough to relieve the axle weight from the springs. (11) Remove the spring U-bolts from the plate brackets.

J (12) Loosen BUT DO NOT REMOVE the bolts that attach the spring rear pivot at the frame rail brackets. This will allow the springs to pivot without binding on the bushings. (13) Disconnect shackle from the springs and lower the springs to the surface. (14) Lower the jack enough to remove the axle.

INSTALLATION CAUTION: Suspension components with rubber bushings should be tightened with the vehicle at normal height. It is important to have the springs supporting the weight of the vehicle when the fasteners are torqued. If springs are not at their normal ride position, vehicle ride comfort could be affected and premature bushing wear may occur. Rubber bushings must never be lubricated. (1) Support the axle on a hydraulic jack under the differential. Position the axle under the vehicle. (2) Raise the springs and install the spring shackle bolts. Do not tighten at this time. (3) Lower the axle and align the spring center bolts with the locating holes in the axle pads and plate brackets. (4) Install the spring U-bolts through the plate brackets and tighten to 122 Nzm (90 ft. lbs.) torque. (5) Connect the track bar to the axle bracket and install the bolt. Do not tighten at this time. It is important that the springs support the weight of the vehicle when the track bar is connected. If springs are not at their usual position, the vehicle ride comfort could be affected. (6) Install the shock absorber and tighten the nut to 61 Nzm (45 ft. lbs.) torque. (7) Install the stabilizer bar link to the axle bracket. Tighten the nut to 61 Nzm (45 ft. lbs.) torque. (8) Install the tie rod to the steering knuckles and tighten the nuts to 47 Nzm (35 ft. lbs.) torque. Install the steering damper to the axle bracket and tighten the bolt to 75 Nzm (55 ft. lbs.) torque. (9) Install the brake components and ABS brake sensor (if equipped). Refer to Group 5—Brakes. (10) Connect the vent hose to the tube fitting and axle shift motor vacuum harness. (11) Align the reference marks and connect the drive shaft to the axle yoke. Tighten the U-joint clamp bolts to 19 Nzm (14 ft. lbs.) torque. (12) Check differential lubricant and add if necessary. (13) Install the wheel and tire assemblies. (15) Remove the supports and lower the vehicle. (16) Tighten the spring rear pivot bolt/nut to 142 Nzm (105 ft. lbs.) torque. Tighten the spring shackle bolt/nut to 135 Nzm (100 ft. lbs.) torque.


FRONT SUSPENSION AND AXLE

J (17) Tighten the track bar nut at the axle bracket to 100 Nzm (74 ft. lbs.) torque. (18) Check the front wheel alignment.

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INSTALLATION (1) Apply a light coating of gear lubricant on the lip of pinion seal. Install seal with Installer D-163 and Handle C-4171 (Fig. 4).

PINION SEAL REPLACEMENT REMOVAL (1) Raise and support the vehicle. (2) Remove wheel and tire assemblies. (3) Mark the propeller shaft yoke and pinion yoke for installation alignment reference. (4) Remove the propeller shaft from the yoke. (5) Remove the pinion yoke nut and washer. Use Remover C-452 and Wrench C-3281 to remove the pinion yoke (Fig. 2). (6) Mark the positions of the yoke and pinion gear for installation alignment reference.

Fig. 4 Pinion Seal Installation

Fig. 2 Pinion Yoke Removal (7) Use Remover 7794A and slide hammer to remove the pinion gear seal (Fig. 3).

(2) Align the reference marks and install yoke on the pinion gear with Installer W-162-D. (3) Install a new pinion nut on pinion shaft. Tighten the nut to 217-352 Nzm (160-260 ft. lbs.) (Fig. 5). (4) Align the installation reference marks and attach the propeller shaft to the yoke. (5) Add API grade GL 5 hypoid gear lubricant to the differential housing, if necessary. (6) Install wheel and tire assemblies. (7) Remove support and lower the vehicle.

HUB BEARING AND AXLE SHAFT

Fig. 3 Seal Removal

REMOVAL (1) Raise and support the vehicle. (2) Remove the wheel and tire assembly. (3) Remove the brake components from the axle, refer to Group 5, Brakes. (4) Remove the cotter pin, nut retainer and axle hub nut (Fig. 6). (5) Remove the hub to knuckle bolts (Fig. 6). Remove the hub from the steering knuckle and axle shaft. (6) Remove the disc brake rotor shield from the bearing carrier (Fig. 6). (7) On disconnect axles, remove vacuum shift motor housing. Refer to Vacuum Disconnect Axle in this section. (8) Remove the axle shaft from the housing. Avoid damaging the axle shaft oil seals in the differential.


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FRONT SUSPENSION AND AXLE

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Fig. 6 Hub, Knuckle and Axle Shaft INSTALLATION (1) Thoroughly clean the axle shaft (Fig. 6) and apply a thin film of Mopar Wheel Bearing Grease to the shaft splines, seal contact surface, hub bore. (2) Install the axle shaft into the housing and differential side gears. Avoid damaging the axle shaft oil seals in the differential. (3) Install the hub bearing and brake dust shield to the knuckle. (4) Install the hub to knuckle bolts and tighten to 102 Nzm (75 ft. lbs.) torque. (5) Install the hub washer and nut. Tighten the hub nut to 237 Nzm (175 ft. lbs.) torque. Install the nut retainer and a new cotter pin (Fig. 6). (6) Install the brake components, refer to Group 5, Brakes. (7) Install the wheel and tire assembly. (8) Remove support and lower the vehicle.

AXLE SHAFT—CARDAN U-JOINT DISASSEMBLY Single cardan U-joints are not serviceable. If defective, they must be replaced as a unit. If the bearings, seals, spider or bearing caps are damaged or worn, replace the complete U-joint. CAUTION: Clamp only the forged portion of the yoke in the vise. Also, to avoid distorting the yoke, do not over tighten the vise jaws. (1) Remove the bearing cap retaining snap rings (Fig. 7). It can be helpful to saturate the bearing caps with penetrating oil prior to removal.

Fig. 7 Axle Shaft Outer U-Joint (2) Locate a socket that is larger in diameter than the bearing cap. Place the socket (receiver) against the yoke and around the perimeter of the bearing cap to be removed. Locate a socket that is smaller in diameter than the bearing cap. Place the socket (driver) against the opposite bearing cap. Position the yoke with the sockets in a vise (Fig. 8). (3) Compress the vise jaws to force the bearing cap into the larger socket (receiver). (4) Release the vise jaws. Remove the sockets and bearing cap that was partially forced out of the yoke. (5) Repeat the above procedure for the remaining bearing cap.


FRONT SUSPENSION AND AXLE

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VACUUM DISCONNECT AXLE—YJ VEHICLES VACUUM CONTROL SYSTEM The disconnect axle control system consists of; • Vacuum control switch on the transfer case • Air vent filter • Shift motor • Indicator switch • Vacuum switch • Check valve • Vacuum harness (Fig. 9, 10)

Fig. 8 Yoke Bearing Cap Removal (6) Remove the remaining bearing cap, bearings, seals and spider from the propeller shaft yoke.

CLEANING AND INSPECTION (1) Clean all the U-joint yoke bores with cleaning solvent and a wire brush. Ensure that all the rust and foreign matter are removed from the bores. (2) Inspect the yokes for distortion, cracks and worn bearing cap bores. (3) Replace the complete U-joint if any of the components are defective. ASSEMBLY (1) Pack the bearing caps 1/3 full of wheel bearing lubricant. Apply extreme pressure (EP), lithium-base lubricant to aid in installation. (2) Position the spider in the yoke. Insert the seals and bearings. Tap the bearing caps into the yoke bores far enough to hold the spider in position. (3) Place the socket (driver) against one bearing cap. Position the yoke with the socket wrench in a vise. (4) Compress the vise to force the bearing caps into the yoke. Force the caps enough to install the retaining clips. (5) Install the bearing cap retaining clips. (6) Install the axle shaft, refer to Hub Bearing and Axle Shaft installation.

Fig. 9 Vacuum Control System Refer to Group 21—Transmissions for additional information involving the Command-Trac System Transfer Case.


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FRONT SUSPENSION AND AXLE

Fig. 10 Vacuum Hose Routing

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FRONT SUSPENSION AND AXLE DISCONNECT AXLE/SHIFT MOTOR DIAGNOSIS

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FRONT SUSPENSION AND AXLE DISCONNECT AXLE/SHIFT MOTOR DIAGNOSIS (CONT’D)

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FRONT SUSPENSION AND AXLE

J SHIFT MOTOR—REMOVAL/DISASSEMBLY (1) Disconnect the vacuum and wiring connector from the shift housing. (2) Remove indicator switch. (3) Remove the shift motor housing cover, gasket and shield from the housing (Fig. 11).

Fig. 11 Shift Motor Housing and Shift Collar (4) Remove the E-clips from the shift motor housing and shaft. Remove shift motor and shift fork from the housing (Fig. 12).

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(3) Install the E-clips on the shift motor shaft and housing. (4) Install the shift motor housing gasket and cover. Ensure the shift fork is correctly guided into the shift collar groove. (5) Install the shift motor housing shield and attaching bolts. Tighten the bolts to 11 Nzm (101 in. lbs.) torque. (6) Add 148 ml (5 ounces) of API grade GL 5 hypoid gear lubricant to the shift motor housing. Add lubricant through indicator switch mounting hole. (7) Install indicator switch, electrical connector and vacuum harness.

INTERMEDIATE AXLE SHAFT—REMOVAL/ DISASSEMBLY Service to the Disconnect axle seals and bearing require the use of Tool Set 6288 (J34659) and Seal Installer 6228. (1) Remove the vacuum motor housing. Refer to Shift Motor Removal in this section. (3) Remove the outer axle shaft. Refer to Hub Bearing and Axle Shaft in this section. (4) Remove shift collar and intermediate axle shaft. (5) Remove the inner axle shaft seal from the shift motor housing (Fig. 13).

Fig. 12 Vacuum Shift Motor Components

Fig. 13 Axle Shaft Inner Seal Removal

(5) Remove the O-ring seal from the shift motor shaft. (6) Clean and inspect all components. If any component is excessively worn or damaged, it should be replaced.

(6) Remove the intermediate axle shaft bearing (Fig. 14).

ASSEMBLY/INSTALLATION (1) Install a new O-ring seal on the shift motor shaft. (2) Insert the shift motor shaft through the hole in the housing and shift fork. The shift fork offset should be toward the differential.

ASSEMBLY/INSTALLATION (1) Position the bearing on installation tool. Seat the bearing in the housing bore (Fig. 15). (2) Clean the inside perimeter of the axle shaft tube with fine crocus cloth. (3) Apply a light film of oil to the inside lip of the new axle shaft seal. (4) Install the inner axle seal (Fig. 16, 17). The axle shaft seal primary installation tool 6228-1 will only force the seal partially into the


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FRONT SUSPENSION AND AXLE

Fig. 14 Bearing Removal Tool Installed

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Fig. 17 Secondary Installation of Seal (Step Two) (5) Insert the intermediate axle shaft into the differential side gear. (6) Install the shift collar on the splined end of the intermediate axle shaft. (7) Lubricate the splined end of the intermediate axle shaft with multi-purpose lubricant (Fig. 18).

Fig. 15 Intermediate Shaft Bearing Installation axle shaft tube bore. The axle shaft seal secondary installation tool 6228-3 must be used to completely seat the seal in the axle shaft tube bore. After seal installation, inspect that the seal is NOT distorted or cocked in the tube.

Fig. 18 Shift Collar Installation CAUTION: Apply all-purpose lubricant to the axle shaft splines to prevent damage to the seal during axle shaft installation. (8) Insert the axle shaft into the tube. Engage the splined-end of the shaft with the shift collar. Refer to Hub Bearing and Axle Shaft in this section. (9) Install the vacuum motor housing. Refer to Shift Motor Installation in this section.

STEERING KNUCKLE AND BALL STUDS

Fig. 16 Primary Installation of Seal (Step One)

Ball Stud service procedures below require removal of the hub bearing and axle shaft. Removal and installation of upper and lower ball stud requires use of Tool Kit 6289 (J34503-A).


FRONT SUSPENSION AND AXLE

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The lower ball stud has two different designs. For this reason installer 6752 will also be needed. Check installers for proper fit.

KNUCKLE REMOVAL (1) Remove hub bearing and axle shaft refer to the Removal procedure. (2) Disconnect the tie-rod or drag link end from the steering knuckle arm. Remove the ABS sensor wire and bracket from knuckle. (3) Remove the cotter pins from the upper and lower ball studs. Remove the upper and lower ball stud nuts. (4) Strike the steering knuckle with a brass hammer to loosen. Remove knuckle from axle tube yokes (Fig. 19). UPPER BALL STUD REPLACEMENT (1) Position tools as shown to remove and install ball stud (Fig. 20). LOWER BALL STUD REPLACEMENT (1) Position tools as shown to remove and install ball stud (Fig.21). Because there are two different designs for the lower ball studs try both installers for proper fit. KNUCKLE INSTALLATION (1) Position the steering knuckle on the ball studs.

Fig. 19 Steering Knuckle Removal/Installation (2) Install and tighten the bottom retaining nut to 109 Nzm (80 ft. lbs.) torque. Install new cotter pin. (3) Install and tighten the top retaining nut to 101 Nzm (75 ft. lbs.) torque. Install new cotter pin.

Fig. 20 Upper Ball Stud Remove/Install


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Fig. 21 Lower Ball Stud Remove/Install (4) Install the Hub Bearing and Axle Shaft according to the installation procedure. (5) Reconnect the tie-rod or drag link end onto the steering knuckle arm. Install the ABS sensor wire and bracket to the knuckle, refer to Group 5 Brakes.

AXLE BUSHING REPLACEMENT Refer to Axle Bushing Replacement in the Front Suspension section.

DIFFERENTIAL REMOVAL To service the differential the axle assembly and axle shafts must be removed. Refer to the removal procedures in this Group. (1) Note the installation reference letters stamped on the bearing caps and housing machined sealing surface (Fig. 22). (2) Remove the differential bearing caps. (3) Position Spreader W-129-B with the tool dowel pins seated in the locating holes (Fig. 23). Install the holddown clamps and tighten the tool turnbuckle finger-tight. (4) Install a pilot stud at the left side of the differential housing. Attach Dial Indicator to housing pilot stud. Load the indicator plunger against the opposite side of the housing (Fig. 23) and zero the indicator.

Fig. 22 Bearing Cap Identification CAUTION:Do not spread over 0.38 mm (0.015 in). If the housing is over-separated, it could be distorted or damaged. (5) Separate the housing enough to remove the case from the housing. Measure the distance with the dial indicator (Fig. 23). (6) Remove the dial indicator. (7) Pry the differential case loose from the housing. To prevent damage, pivot on housing with the end of the pry bar against spreader (Fig. 24).


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Fig. 23 Spread Differential Housing

Fig. 25 Axle Seal Installation (2) Install the inner axle seal on Tool 6228-1 (Fig. 26). (3) Thread the reverse side of Installer 6228-1 tightly onto the threaded rod tool (Fig. 26). (4) Press the seal into position.

Fig. 24 Differential Removal (8) Remove the case from housing. Mark or tag bearing cups indicating which side they were removed. Remove spreader from housing.

INNER AXLE SHAFT OIL SEAL REPLACEMENT SELECT-TRAC (1) Remove the inner axle shaft seals with a pry bay. (2) Install oil seals with Discs 6764 and Turnbuckle D-112-A (Fig. 25). Tighten tool until disc bottoms in housing. COMMAND-TRAC—LEFT-SIDE (1) Remove the inner axle shaft seal with a pry bay.

Fig. 26 Left Side Seal Installation

DIFFERENTIAL DISASSEMBLY (1) Remove the bearings from the differential case with Press C-293-PA, Plug C-293-3, Adapter C-293-39 (Fig. 27).


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Place adapter rings so they do not damage the bearing cage.

J (4) Use a drift to remove the pinion gear mate shaft lock pin (Fig. 29).

Fig. 29 Mate Shaft Lock Pin Removal (5) Remove the mate shaft with a drift and hammer (Fig. 30).

Fig. 27 Differential Bearing Removal (2) Remove bearing shims from case hubs and mark them (with hub identity) for assembly reference. Record the thickness of the shims. (3) Clamp the differential case in a vise equipped with soft jaws. Remove and discard the ring gear bolts. Tap the ring gear with a rawhide or plastic mallet and remove (Fig. 28).

Fig. 30 Mate Shaft Removal (6) Rotate the differential side gears and remove the pinion mate gears and thrust washers (Fig. 31). (7) Remove the differential side gears and thrust washers. (8) Remove the case from the vise.

PINION REMOVAL/DISASSEMBLY

Fig. 28 Ring Gear Removal

(1) Remove the pinion yoke nut and washer. Use Remover C-452 and Wrench C-3281 to remove the pinion yoke (Fig. 32). (2) Remove the pinion gear seal with a slide hammer or pry out with bar.


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Fig. 31 Pinion Mate Gear Removal

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Fig. 33 Remove Pinion Gear

Fig. 32 Pinion Yoke Removal (3) Drive out pinion gear from housing with rawhide or plastic hammer (Fig. 33). Catch the pinion with your hand to prevent it from falling and being damaged. This will damage the front bearing rollers and bearing cup. The front bearing and cup must be replaced. Remove preload shims and record the thickness. (4) Remove front bearing from housing. (5) Remove the front pinion bearing cup and seal with Remover D-147 and Handle C-4171 (Fig. 34). (6) Remove the rear bearing cup from housing (Fig. 35). Use Remover D-149 and Handle C-4171. (7) Remove the inner bearing from the pinion with Puller C-293-PA and Adapter C-293-39 (Fig. 36). Place adapter rings so they do not damage the bearing cage.

Fig. 34 Front Bearing Cup Removal (8) Remove the oil slinger from the pinion gear shaft. Save the slinger it is used as select shim for pinion depth.

CLEANING/INSPECTION Wash differential components with cleaning solvent and dry with compressed air. Do not steam clean the differential components. Wash bearings with solvent and towel dry, or dry with compressed air. DO NOT spin bearings with


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J • Raised metal on shoulders of cup bores should be removed with a hand stone. • Wear or damage to pinion gear mate shaft, pinion gears, side gears and thrust washers. Replace as a matched set only. • Worn or chipped teeth to ring and pinion gears. • Damaged bolt threads to ring gear. Replaced as a matched set only. • Pinion yoke for cracks, worn splines, pitted areas, and a rough/corroded seal contact surface. Repair or replace the as necessary.

DIFFERENTIAL ASSEMBLY

Fig. 35 Rear Bearing Cup Removal

ASSEMBLY (1) Install the following components in the differential case (Fig. 37). • Differential side gears and thrust washers • Pinion gears and thrust washers • Pinion gear mate shaft (align holes in shaft and case) (2) Install and seat the locking roll pin in the differential case and mate shaft with a punch and hammer (Fig. 37). Peen metal part of case over pin in two places 180 degrees apart. If replacement gears and thrust washers were installed, it is not necessary to measure the gear backlash. Correct fit is due to close machining tolerances during manufacture.

Fig. 36 Inner Bearing Removal compressed air. Cup and bearing must be replaced as a matched sets only. Clean axle shaft tubes and oil channels with clean cloth. Inspect for; • Smooth appearance with no broken/dented surfaces on the bearing rollers or the roller contact surfaces. • Bearing cups must not be distorted or cracked. • Machined surfaces should be smooth and without any raised edges.

Fig. 37 Mate Shaft Pin Installation (3) Invert the differential case and start two ring gear bolts. This will provide case-to-ring gear bolt hole alignment. (4) Install new ring gear bolts and alternately tighten to 95-122 Nzm (70-90 ft. lbs.) torque (Fig. 38).


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THE BUTTON END ON THE PINION GEAR HEAD IS NO LONGER A MACHINED-TO-SPECIFICATIONS SURFACE. DO NOT USE THIS SURFACE FOR PINION DEPTH SET-UP OR CHECKING (Fig. 40).

Fig. 38 Ring Gear Bolt Installation

Fig. 40 Pinion Gear Head

(5) Lubricate all differential components with hypoid gear lubricant.

Compensation for depth variance is achieved by a selected thickness oil slinger (production) or shims (service). The slinger is placed between the inner pinion bearing cone and gear head (Fig. 41). The shim pack is placed under the inner (rear) bearing cup for service. To change the pinion adjustment, shims are available in thicknesses of 0.003, 0.005, and 0.010 inch. The oil slinger or baffle must be measured and the thickness included with the total shim pack.

PINION GEAR DEPTH INFORMATION Ring and pinion gears are supplied as matched sets only. The identifying numbers for the ring and pinion gear are etched into the face of each gear (Fig. 39). A plus (+) number, minus (-) number or zero (0) is etched into the face of the pinion gear. This number is the amount (in thousandths of an inch) the depth varies from the standard depth setting of a pinion etched with a (0). The standard setting from the centerline of the ring gear to the back face of the pinion is 92.1 mm (3.625 inches) for Model 30 axles (Fig. 40). The standard depth provides the best teeth contact pattern.

Fig. 39 Pinion Gear ID Numbers

Fig. 41 Shim Locations


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PINION GEAR DEPTH VARIANCE

New gear set: note the depth variance etched into both the original and the replacement pinion gear. Add or subtract the thickness of the original depth shims to compensate for the difference in the depth variances. Refer to the Depth Variance charts. Note where Old and New Pinion Marking columns intersect. Intersecting figure represents plus or minus amount needed. For example, if old pinion is plus (+) 1 and the new pinion is minus (-) 3, intersecting figure is (+)0.004 inch (0.10mm). Add this amount to the original shim. Or if the old pinion is (-) 3 and the new pinion is (-) 2, intersecting figure is (-)0.001 inch (0.025mm). Subtract this amount from original shim. Refer to the Pinion Gear Depth Variance Chart.

DIFFERENTIAL AND PINION MEASUREMENT DIFFERENTIAL ZERO END PLAY MEASUREMENT (1) Place Master Differential Bearing D-134 (D-348) on the case hubs (Fig. 42). Install differential case into housing. (2) Install a pilot stud at the right side of housing. Attach Dial Indicator to the pilot stud. Load indicator plunger against the back of the ring gear (Fig. 43). (3) Insert a small pry bar between the bearing cap and left side of differential case. Pry the case as far as possible to right side (Fig. 43). Zero the dial indicator pointer. (4) Pry the case to left side and record the travel distance.

Fig. 42 Master Bearing Tools On Hubs The measurement above is the shim thickness necessary for case zero end-play. The total thickness will be determined during the ring gear backlash adjustment. (5) Remove indicator, pilot stud and differential case from housing.

PINION GEAR DEPTH MEASUREMENT Pinion gear depth measurement is necessary when;


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Fig. 45 Pinion Front Bearing Cup Installation (2) Install the bearing cup with Installer D-146 and Driver Handle C-4171 (Fig. 46). Ensure cup is correctly seated.

Fig. 43 Differential Case End Play Measurement • Axle housing or differential case is replaced • Pinion select shim pack is unknown • Ring and pinion gears are replaced Measurements are done with pinion cups and pinion bearings installed in housing. Take measurements with Pinion Gauge Set 6774, Pinion Block 6733 and Dial Indicator C-3339 (Fig. 44).

Fig. 46 Pinion Rear Bearing Cup Installation

Fig. 44 Pinion Gear Depth Gauge Tools (1) Install the pinion front bearing cup with Installer D-144 and Handle C-4171 (Fig. 45).

(3) Assemble Pinion Gauge Set, Pinion Block and pinion bearings. Install assembly into differential pinion gear bore and hand tighten cone (Fig. 47). (4) Place Arbor Disc 6732 on Arbor D-115-3 and position in the bearing cradles (Fig. 48). Install differential bearing caps on Arbor Discs and tighten caps snug only. Arbor Discs have different steps to fit other axle sizes. Pick correct size step for axle being serviced. (5) Firmly place Scooter Block and Dial Indicator on pinion height block tool and zero the dial indicator pointer. (6) Slide the Scooter Block across the arbor while


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J The plunger travel, plus or minus the variance etched in the gear, is the required thickness for the depth shims. (7) Measure the thickness of each depth shim with a micrometer. Combine the shims necessary for total required shim pack thickness. Include oil slinger or baffle thickness with the total shim pack thickness. (8) Remove the measurement tools from the differential housing.

PINION GEAR ASSEMBLY/INSTALLATION

Fig. 47 Pinion Height Block

(1) Remove rear pinion bearing cup with Remover D-149 and Handle C-4171. Place shims (and baffle if equipped) in the pinion gear rear bearing bore. Install the bearing cup with Installer D-146 and Driver Handle C-4171. Ensure cup is correctly seated. (3) Install rear bearing and oil slinger on pinion gear with Installer W-262 until completely seated (Fig. 50).

Fig. 48 Gauge Tools In Housing observing indicator (Fig. 49). Record the longest travel distance, whether inward (-) or outward (+), indicated by the pointer.

Fig. 50 Pinion Rear Bearing Installation

Fig. 49 Pinion Depth Measurement

(4) Assemble preload shims onto pinion shaft. (5) Install pinion front bearing cone into cup and end yoke thrust washer. (6) Apply a light coat of gear lubricant on lip of new pinion seal. Install seal with Installer D-163 and Handle C-4171 (Fig. 51). (7) Install pinion gear into differential housing. (9) Install yoke with Installer W-162-D and Wrench C-3281 (Fig. 52). (10) Install the yoke washer and old nut on the pinion gear. Use Flange Wrench C-3281 to retain the yoke (Fig. 53). Tighten nut to 216-352 Nzm (160-260 ft.lbs.) torque.


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Fig. 51 Pinion Seal Installation

Fig. 53 Tightening Pinion Nut

Fig. 52 Pinion Yoke Installation

Fig. 54 Check Pinion Gear Torque

(11) Check bearing rotating torque with an inch pound torque wrench (Fig. 54).If torque to rotate is within specification, remove old nut and install new nut. The torque necessary to rotate the pinion gear should be; • Original Bearings: 1 to 3 Nzm (10 to 20 in. lbs.). • New Bearings: 2 to 5 Nzm (15 to 35 in. lbs.). (12) If rotating torque is high, add shims to decrease torque. If rotating torque is low, remove shims to increase torque.

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DIFFERENTIAL SHIM PACK MEASUREMENT AND ADJUSTMENT (1) Place Master Differential Bearing D-134 (D-348) on the case hubs. (2) Install a pilot stud at the left side of housing. Attach Dial Indicator to housing. Load the indicator plunger against the back of the ring gear (Fig. 55). Ensure ring and pinion gear teeth are tightly meshed. Zero the indicator.


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Fig. 55 Shim Pack Measurement (3) Insert a small pry bar between the bearing cap and left side of differential case. Pry the case as far as possible to right side (Fig. 55). Zero the dial indicator pointer. (4) Repeat the measurement several times to check consistency. Record the travel distance. The measurement above shows shim thickness necessary to eliminate ring gear backlash. Subtract this thickness from case zero end-play shim thickness (Fig. 56). The shims must be placed at the ring gear side between the case and bearing. (5) Remove indicator and pilot stud. (6) Remove the differential case from housing. (7) Remove the master bearing tools from the differential case hubs. (8) Position the backlash shims (with determined thickness) on case hub (ring gear side). Install bearing on the hub with Bearing Installer C-3716-A and Driver Handle C-4171 (Fig. 57). (9) Position the remaining zero end-play shims on hub at opposite side of case. Include an additional 0.015 in. (0.38 mm) thick shim on this hub. This will provide the required differential bearing preload. (10) Install bearings on hubs with Installer C-3716-A and Handle C-4171 (Fig. 57). (11) Match each bearing cup with bearing (original). Install the cups on the bearings.

DIFFERENTIAL INSTALLATION (1) Position Spreader W-129-B with the tool dowel pins seated in the locating holes (Fig. 58). Install the holddown clamps and tighten the tool turnbuckle finger-tight.

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Fig. 56 Shim Pack Calculations

Fig. 57 Differential Bearing Installation (2) Install a pilot stud at the left side of the differential housing. Attach Dial Indicator to housing pilot stud. Load the indicator plunger against the opposite side of the housing (Fig. 58) and zero the indicator. CAUTION: Do not spread over 0.38 mm (0.015 in). If the housing is over-separated, it could be distorted or damaged.


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Fig. 58 Spread Differential Housing

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Fig. 60 Differential Bearing Cap Reference Letters

(3) Spread the housing enough to install the case in the housing. Measure the distance with the dial indicator (Fig. 58). (4) Remove the dial indicator. (5) Install case in the housing. Tap the differential case to ensure the bearings are fully seated (Fig. 59). Remove the spreader.

Fig. 61 Ring Gear Backlash Measurement

Fig. 59 Differential Installation (6) Install the bearing caps at their original locations (Fig. 60). Tighten the bearing cap bolts to 61 Nzm (45 ft. lbs.) torque.

BACKLASH AND CONTACT PATTERN ANALYSIS (1) Rotate assembly several revolutions to seat bearings. Measure backlash at three equally spaced locations around the perimeter of the ring gear with a dial indicator (Fig. 61).

The ring gear backlash must be within 0.12 0.20 mm (0.005 - 0.008 inch). It cannot vary more than 0.05 mm (0.002 inch) between the points checked. If backlash must be adjusted, transfer shims from one side of carrier to the other side. Adjust the backlash accordingly (Fig. 62). DO NOT INCREASE THE TOTAL SHIM PACK THICKNESS, EXCESSIVE BEARING PRELOAD AND DAMAGE WILL OCCUR. If the mesh and backlash steps have been followed, good gear teeth contact patterns should exist. The ring gear teeth contact patterns will show if the pinion gear depth is correct. It will also show if the ring gear backlash has been adjusted correctly. The backlash must be maintained within the specified limits until the correct tooth contact patterns are obtained. (2) Apply a thin coat of hydrated ferric oxide (yellow oxide of iron) to the drive and coast side of the ring gear teeth.


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J (4) Note patterns in compound. Refer to (Fig. 63) for interpretation of contact patterns and adjust accordingly.

FINAL ASSEMBLY (1) Install the axle shafts. Refer to Axle Shaft Installation in this Group. (2) Scrape the residual sealant from the housing and cover mating surfaces. Clean the mating surfaces with mineral spirits. Apply a bead of MOPARt Silicone Rubber Sealant on the housing cover (Fig. 64). Allow the sealant to cure for a few minutes. Install the housing cover within 5 minutes after applying the sealant. If not installed the sealant must be removed and another bead applied. (3) Install the cover on the differential with the attaching bolts. Install the identification tag. Tighten the cover bolts with 41 Nzm (30 ft. lbs.) torque.

Fig. 62 Backlash Shim Adjustment (3) Rotate the ring gear one complete revolution in both directions while a load is being applied. Insert a pry bar between the differential housing and the case flange to load gears. This will produce a distinct contact patterns on both the drive side and coast side of the ring gear teeth.

CAUTION: Overfilling the differential can result in lubricant foaming and overheating. (4) Refill the differential housing with the specified quantity of MOPARt Hypoid Gear Lubricant. (5) Install the fill hole plug and tighten to 34 Nzm (25 ft. lbs.) torque.


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Fig. 63 Gear Tooth Contact Patterns

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Fig. 64 Typical Housing Cover With Sealant

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AXLE SPECIFICATIONS MODEL 30 FRONT AXLE Axle Type ........................................................Hypoid Lubricant................SAE Thermally Stable 80W-90 Lube Capacity YJ .....................................................1.65 L (3.76 pts.) XJ .....................................................1.48 L (3.13 pts.) Axle Ratio...................................3.07 3.55 3.73 4.10 Differential

Side Gear Clearance .0.12-0.20mm (0.005-0.008 in.) Ring Gear Diameter .....................................18.09 cm (7.125 in.) Backlash.........................0-0.15 mm (0.005-0.008 in.) Pinion Std. Depth ...................92.1 mm (3.625 in.) Pinion Bearing Preload Original Bearing ..................1-2 Nzm (10-20 in. lbs.) New Bearing......................1.5-4 Nzm (15-35 in. lbs.)

TORQUE SPECIFICATIONS XJ FRONT SUSPENSION COMPONENTS DESCRIPTION ................................................TORQUE Shock Absorber Upper Nut ......................................11 Nzm (8 ft. lbs.) Lower Nut....................................23 Nzm (17 ft. lbs.) Suspension Arm Upper Front Nut.....................................74 Nzm (55 ft. lbs.) Rear Nut ......................................89 Nzm (66 ft. lbs.) Suspension Arm Lower Front and Rear Nut..................115 Nzm (85 ft. lbs.) Stabilizer Bar Clamp Bolt...................................54 Nzm (40 ft. lbs.) Link Upper Nut ..........................36 Nzm (27 ft. lbs.) Link Lower Nut ..........................95 Nzm (70 ft. lbs.) Track Bar Ball Stud Nut ..............................81 Nzm (60 ft. lbs.) Axle Bracket Bolt......................100 Nzm (74 ft. lbs.) Track Bar Bracket Bolts............................................125 Nzm (92 ft. lbs.) Nut..............................................100 Nzm (74 ft. lbs.) Support Bolts...............................42 Nzm (31 ft. lbs.)

YJ FRONT SUSPENSION COMPONENTS DESCRIPTION ................................................TORQUE Shock Absorber Upper Nut......................................13 Nzm (9 ft. lbs.)

Lower Nut....................................61 Nzm (45 Stabilizer Bar Clamp Bolt...................................41 Nzm (30 Link Nut ......................................61 Nzm (45 Track Bar Frame Bracket Nut.................142 Nzm (105 Axle Bracket Nut ......................100 Nzm (74 Spring U-Bolt Nut .................................122 Nzm (90 Front Shackle Bolt..................135 Nzm (100 Rear Pivot Bolt........................142 Nzm (105

ft. lbs.) ft. lbs.) ft. lbs.) ft. lbs.) ft. lbs.) ft. lbs.) ft. lbs.) ft. lbs.)

MODEL 30 AXLE DESCRIPTION ................................................TORQUE Fill Hole Plug ...........................34 Nzm (25 ft. lbs.) Diff. Cover Bolt ........................41 Nzm (30 ft. lbs.) Bearing Cap Bolt .....................61 Nzm (45 ft. lbs.) Ring Gear Bolt .............95-122 Nzm (70-90 ft. lbs.) Shift Motor Bolt .........................11 Nzm (8 ft. lbs.) Axle Nut .................................237 Nzm (175 ft. lbs.) Wheel Brg. Bolt ......................102 Nzm (75 ft. lbs.) Lower Ball Stud .....................108 Nzm (80 ft. lbs.) Upper Ball Stud .....................101 Nzm (75 ft. lbs.) ABS Sensor Bolt ......................11 Nzm (96 in. lbs.)


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REAR SUSPENSION AND AXLES CONTENTS page

page

8 1/4 AXLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 AXLE NOISE/VIBRATION DIAGNOSIS . . . . . . . . . 9 AXLE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . 51 GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1 MODEL 35 AXLE . . . . . . . . . . . . . . . . . . . . . . . . 13

TORQUE SPECIFICATIONS . . . . . . . . . . . . . . . . 51 TRAC-LOK DIFFERENTIAL . . . . . . . . . . . . . . . . . 45 XJ SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . 3 YJ SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . 6

GENERAL INFORMATION SUSPENSION COMPONENTS The Jeep rear suspension is comprised of; Drive axle Leaf springs Dual-action shock absorbers Track bar (YJ vehicles) Stabilizer bar (XJ vehicles) Jounce bumpers The rear suspension design uses semi-elliptic multi-leaf springs and a solid drive axle. The forward end of the springs are mounted to the frame rail hangers through rubber bushings. The bushings isolate road noise as the springs move. The rearward end of the springs are attached to the frame by the use of shackles. Again the spring and shackles use rubber bushings to isolate road noise. The shackles allow the springs to change their length as the vehicle moves over various road conditions. The spring and axle travel is limited through the use of bumpers mounted on frame. All suspension components that use bushings should be tightened with the vehicle at normal ride height. If the springs are not at normal ride position, vehicle ride comfort could be affected. Rubber bushings must never be lubricated. The springs are attached to the axle pads with Ubolts and plates. The springs use a center bolt that holds the spring leafs in position. The bolt is also used to locate the spring assembly to the axle pad. Ride control is accomplished through the use of dual-action shock absorbers. The shocks dampen the jounce and rebound as the vehicle travels over various road conditions. The top of shock absorbers are bolted to the frame bracket. The bottom of the shocks are bolted to the axle bracket. The stabilizer bar on the XJ is used to minimize vehicle rear sway during turns. The bar helps the vehicle maintain a flat attitude to the road surface. The bar extends across the underside of the chassis and connects to the frame rails. The links are connected • • • • • •

to the axle brackets. All mounting points of the stabilizer bar are isolated by bushings. The track bar on the YJ is used to minimize rear axle side-to-side movement. The track bar is attached to the frame rail bracket and axle bracket and is isolated with bushings. The jounce bumpers are used to limit the jounce and rebound travel of the suspension.

AXLES The Model 35 axle is standard for XJ and YJ vehicles. The 8 1/4 axle is available in XJ vehicles without ABS brakes. The Model 35 and 8 1/4 axle housings has a cast iron center section. Two steel axle shaft tubes are pressed into the differential housing and welded. It is not necessary to remove the axle from the vehicle for service. A removable differential cover is provided for routine vehicle service. If the differential housing is damaged, the complete axle assembly can be removed. For complete drive axle assembly removal and installation refer to Drive Axle Assembly Replacement in this Group.

IDENTIFICATION Model 35 axle has the assembly part number and gear ratio listed on a tag. The tag is attached to the left side of the housing cover (Fig. 1). Build date identification codes on axles are stamped on the axle shaft tube cover side. The Model 35 axle has a flat housing cover gasket flange at the outer edge (Fig. 1). The 8 1/4 axle has the build date code and gear ratio tags attached to the housing cover (Fig. 2). The housing cover gasket has a rolled gasket flange at the outer edge (Fig. 2). • The Model 35 axle has shaft tubes that are 2.625 inch (66.67 mm) in diameter. • The 8 1/4 axle has axle shaft tubes that are 3.0inch (76.2 mm) in diameter.


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J • The ring gear (bolted to the differential case) rotates the case • The differential pinion gears (mounted on the pinion mate shaft in the case) rotate the side gears • The side gears (splined to the axle shafts) rotate the shafts During straight-ahead driving, the differential pinion gears do not rotate on the pinion mate shaft. This occurs because input torque applied to the gears is divided and distributed equally between the two side gears. As a result, the pinion gears revolve with the pinion mate shaft but do not rotate around it (Fig. 3).

Fig. 1 Model 35 Differential Cover

Fig. 3 Differential Operation—Straight-Ahead Driving When turning corners, the outside wheel must travel a greater distance than the inside wheel in order to complete a turn. The difference must be compensated for, to prevent the tires from scuffing and skidding through turns. To accomplish this, the differential allows the axle shafts to turn at unequal speeds (Fig. 4). In this instance, the input torque applied to the pinion gears is not divided equally. The pinion gears now rotate around the pinion mate shaft in opposite directions. This allows the side gear and axle shaft attached to the outside wheel to rotate at a faster speed.

Fig. 2 8 1/4 Differential Cover STANDARD DIFFERENTIAL OPERATION The differential gear system divides the torque between the axle shafts. It allows the axle shafts to rotate at different speeds when turning corners. Each differential side gear is splined to an axle shaft. The pinion gears are mounted on a pinion mate shaft and are free to rotate on the shaft. The pinion gear is fitted in a bore in the differential case and is positioned at a right angle to the axle shafts. In operation, power flow occurs as follows: • The pinion gear rotates the ring gear

Fig. 4 Differential Operation—On Turns


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XJ SUSPENSION INDEX page

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Leaf Spring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Leaf Spring Eye Bushing Replacement . . . . . . . . . . 5 Shock Absorber . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Spring and Shock Diagnosis . . . . . . . . . . . . . . . . . . 3 Stabilizer Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

SPRING AND SHOCK DIAGNOSIS

Grease and mineral oil-base lubricants will deteriorate the bushing rubber. If the vehicle is used for severe, off-road operation, the springs should be examined regularly. Check for broken and shifted components.

A noise from the shock absorber or spring bushings can be produced if movement between the rubber bushings and the metal occurs. This noise can usually be stopped by tightening the nuts. If the noise persists, inspect for damaged and worn bushings. Repair as necessary. The shock absorbers are not refillable or adjustable. If a malfunction occurs, the shock absorber must be replaced. To test a shock absorber, hold it in an upright position and force the piston into and out of the cylinder four or five times. The action throughout each stroke should be smooth and even. The spring eye and shock absorber bushings do not require any type of lubrication. Do not attempt to stop spring bushing noise by lubricating them.

CAUTION: Suspension components with rubber bushings should be tightened with the vehicle at normal height. It is important to have the springs supporting the weight of the vehicle when the fasteners are torqued. If springs are not at their normal ride position, vehicle ride comfort could be affected and premature bushing wear may occur. Rubber bushings must never be lubricated.

SPRING AND SHOCK ABSORBER DIAGNOSIS


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Fig. 1 Spring & Shock Absorber—XJ Vehicles

SHOCK ABSORBER REMOVAL (1) Remove the shock absorber upper bolts from the frame bracket (Fig. 1). (2) Remove the lower attaching nut and washer from the bracket stud. Remove the shock absorber. INSTALLATION (1) Install the shock absorber lower eye on the spring bracket stud. Install the shock absorber and upper bolts on the frame bracket (Fig. 1). (2) Tighten the lower nut to 62 Nzm (46 ft. lbs.) torque. (3) Tighten the upper bolts to 23 Nzm (17 ft. lbs.) torque.

LEAF SPRING REMOVAL (1) Raise vehicle at frame. (2) Remove the wheel and tire assemblies. (3) Support axle with hydraulic jack to relieve axle weight. (4) Disconnect the shock absorber from the axle bracket or the spring bracket (Fig. 1). (5) Disconnect the stabilizer bar link from the spring bracket stud.

(6) Remove nuts, U-bolts and spring bracket from axle (Fig. 1). (7) Remove nut and bolt attaching spring front eye to shackle (Fig. 1). (8) Remove nut and bolt from spring rear eye (Fig. 1). (9) Remove spring from vehicle.

INSTALLATION (1) Position the spring front eye in the bracket. Loosely install the attaching bolt and nut (Fig. 1). Do not tighten at this time. (2) Position the rear eye in the shackle bracket. Loosely install the attaching bolt and nut (Fig. 1). Do not tighten at this time. (3) Position the axle. Install the spring bracket, U-bolts and nuts (Fig. 1). Tighten the nuts to 70 Nzm (52 ft. lbs.) torque. (4) Connect the stabilizer bar link to the spring bracket. (5) Connect the shock absorber to the axle bracket or spring bracket. (6) Remove the hydraulic jack. (7) Lower the vehicle. (8) Tighten the spring front eye attaching bolts to 148 Nzm (109 ft. lbs.) torque. (9) Tighten the spring rear eye attaching bolts to 108 Nzm (80 ft. lbs.) torque.


REAR SUSPENSION AND AXLES

J LEAF SPRING EYE BUSHING REPLACEMENT (1) Assemble tools shown (Fig. 2). Tighten the nut located at the socket wrench end of the threaded rod until the bushing is forced out.

3-5

STABILIZER BAR REMOVAL (1) Raise and support the vehicle. (2) Disconnect stabilizer bar links from spring brackets (Fig. 3). (3) Disconnect the stabilizer bar brackets from the frame rails. Remove the stabilizer bar and links.

Fig. 2 Spring Eye Bushing Removal (2) Assemble and align the bushing installation tools. (3) Align the bushing with the spring eye. Tighten the nut located at the socket wrench end of the threaded rod. Tighten until the bushing is forced into the spring eye. The bushing must be centered in the spring eye. The ends of the bushing must be flush or slightly recessed within the end surfaces of the spring eye.

Fig. 3 Stabilizer Bar—XJ Vehicles INSTALLATION (1) Position the stabilizer bar links at the spring brackets (Fig. 3). Install the attaching bolts and nuts and tighten to 74 Nzm (55 ft. lbs.) torque. (2) Attach the stabilizer bar to the frame rail brackets with the bolts. Tighten to 54 Nzm (40 ft. lbs.). (3) Remove the supports and lower the vehicle.


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REAR SUSPENSION AND AXLES

J YJ SUSPENSION INDEX page

page

Leaf Spring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Leaf Spring Eye Bushing Replacement . . . . . . . . . . 7 Shock Absorber . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Spring and Shock Diagnosis . . . . . . . . . . . . . . . . . . 6 Track Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

SPRING AND SHOCK DIAGNOSIS

stop spring bushing noise by lubricating them. Grease and mineral oil-base lubricants will deteriorate the bushing rubber. If the vehicle is used for severe, off-road operation, the springs should be examined regularly. Check for broken and shifted components.

A noise from the shock absorber or spring bushings can be produced if movement between the rubber bushings and the metal occurs. This noise can usually be stopped by tightening the nuts. If the noise persists, inspect for damaged and worn bushings. Repair as necessary. The shock absorbers are not refillable or adjustable. If a malfunction occurs, the shock absorber must be replaced. To test a shock absorber, hold it in an upright position and force the piston into and out of the cylinder four or five times. The action throughout each stroke should be smooth and even. The spring eye and shock absorber bushings do not require any type of lubrication. Do not attempt to

CAUTION: Suspension components with rubber bushings should be tightened with the vehicle at normal height. It is important to have the springs supporting the weight of the vehicle when the fasteners are torqued. If springs are not at their normal ride position, vehicle ride comfort could be affected and premature bushing wear may occur. Rubber bushings must never be lubricated.

SPRING AND SHOCK ABSORBER DIAGNOSIS


REAR SUSPENSION AND AXLES

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3-7

Fig. 1 Spring & Shock Absorber—YJ Vehicles

SHOCK ABSORBER REMOVAL (1) Remove the upper attaching nut and washer from the frame bracket stud (Fig. 1). (2) Remove the lower attaching nut, washers and bolt from the axle bracket. Remove the shock absorber (Fig. 1). INSTALLATION (1) Position the shock upper eye on the frame bracket stud. Install the washer and nut (Fig. 1). (2) Position the shock lower eye in the axle shaft tube bracket. Install the lower attaching bolt, washers and nut (Fig. 1). (3) Tighten the upper and lower shock bolts to 61 Nzm (45 ft. lbs.) torque.

LEAF SPRING REMOVAL (1) Raise the vehicle at the frame. (2) Use a hydraulic jack to relieve the axle weight. (3) Remove the wheel and tire. (4) Remove the nuts, the U-bolts and spring bracket from the axle (Fig. 1). (5) Remove the nut and bolt that attaches the spring rear eye to the shackle (Fig. 1). (6) Remove the nut and bolt from the spring front eye (Fig. 1). (7) Remove the spring from the vehicle.

INSTALLATION (1) Position the spring front eye in the bracket. Loosely install the attaching bolt and nut (Fig. 1). Do not tighten at this time. (2) Position the rear eye in the shackle bracket. Loosely install the attaching bolt and nut (Fig. 1). Do not tighten at this time. (3) Align the rear spring center bolt with the locating hole in the rear axle spring pad. (4) Lower the rear axle until it is completely supported by the spring. Ensure that the spring center bolt is seated in the axle spring pad locating hole. Realign the center bolt with the locating hole, if necessary. (5) Position the axle. Install the spring bracket, Ubolts and nuts (Fig. 1). Tighten the U-bolt nuts to 122 Nzm (90 ft. lbs.) torque. (6) Remove the hydraulic jack. (7) Remove the support stands and lower the vehicle. (8) Tighten the spring shackle plate bolts and front spring eye bolt to 135 Nzm (100 ft. lbs.) torque.

LEAF SPRING EYE BUSHING REPLACEMENT (1) Assemble tools shown (Fig. 2). Tighten the nut located at the socket wrench end of the threaded rod until the bushing is forced out. (2) Assemble and align the bushing installation tools. (3) Align the bushing with the spring eye and tighten the nut located at the socket wrench end of the threaded rod. Tighten until the bushing is forced into the spring eye.


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REAR SUSPENSION AND AXLES

J (2) Remove the fasteners that attach the track bar to the frame bracket and axle bracket (Fig. 3).

Fig. 2 Spring Eye Bushing Removal The bushing must be centered in the spring eye. The ends of the bushing must be flush or slightly recessed within the end surfaces of the spring eye.

TRACK BAR REMOVAL (1) Raise the vehicle. Position a hydraulic jack under the axle and raise the axle to relieve the springs of axle weight.

Fig. 3 Track Bar—YJ Vehicles (3) Remove the track bar from the vehicle.

INSTALLATION (1) Position the ends of the track bar in the frame and axle brackets (Fig. 3). (2) Install and tighten the track bar attaching nuts to 168 Nzm (125 ft. lbs.) torque. (3) Remove the supports and lower the vehicle.


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AXLE NOISE/VIBRATION DIAGNOSIS INDEX page

page

Driveline Snap . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Gear and Bearing Noise . . . . . . . . . . . . . . . . . . . . . 9 General Information . . . . . . . . . . . . . . . . . . . . . . . . 9 Limited Slip Differential . . . . . . . . . . . . . . . . . . . . . 10

Low Speed Knock . . . . . . . . . . . . . . . . . . . . . . . . . 10 Rear Axle Alignment . . . . . . . . . . . . . . . . . . . . . . . 10 Vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

GENERAL INFORMATION

GEAR AND BEARING NOISE

Axle bearing problem conditions are usually caused by: • Insufficient or incorrect lubricant • Foreign matter/water contamination • Incorrect bearing preload torque adjustment • Incorrect backlash (to tight) When serviced, the bearings must be cleaned thoroughly. They should be dried with lint-free shop towels. Never dry bearings with compressed air. This will overheat them and brinell the bearing surfaces. This will result in noisy operation after repair. Axle gear problem conditions are usually the result of: • Insufficient lubrication • Incorrect or contaminated lubricant • Overloading (excessive engine torque) or exceeding vehicle weight capacity • Incorrect clearance or backlash adjustment Insufficient lubrication is usually the result of a housing cover leak. It can also be from worn axle shaft or pinion gear seals. Check for cracks or porous areas in the housing or tubes. Using the wrong lubricant will cause overheating and gear failure. Gear tooth cracking and bearing spalling are indicators of this. Axle component breakage is most often the result of: • Severe overloading • Insufficient lubricant • Incorrect lubricant • Improperly tightened components Overloading occurs when towing heavier than recommended loads. Component breakage can occur when the wheels are spun excessively. Incorrect lubricant quantity contributes to breakage. Loose differential components can also cause breakage. Incorrect bearing preload or gear backlash will not result in component breakage. Mis-adjustment will produce enough noise to cause service repair before a failure occurs. If a mis-adjustment condition is not corrected, component failure can result. Excessive bearing preload may not be noisy. This condition will cause high temperature which can result in bearing failure.

GEAR NOISE Axle gear noise can be caused by insufficient lubricant. Incorrect backlash, tooth contact, or worn/damaged gears can cause noise. Gear noise usually happens at a specific speed range. The range is 30 to 40 mph, or above 50 mph. The noise can also occur during a specific type of driving condition. These conditions are acceleration, deceleration, coast, or constant load. When road testing, accelerate the vehicle to the speed range where the noise is the greatest. Shift out-of-gear and coast through the peak-noise range. If the noise stops or changes greatly, check for insufficient lubricant. Incorrect ring gear backlash, or gear damage can cause noise changes. Differential side and pinion gears can be checked by turning the vehicle. They usually do not cause noise in straight-ahead driving. These gears are loaded during vehicle turns. If noise does occur during vehicle turns, the side or pinion gears could be worn or damaged. A worn pinion gear mate shaft can also cause a snapping or a knocking noise. BEARING NOISE The axle shaft, differential and pinion gear bearings can all produce noise when worn or damaged. Bearing noise can be either a whining, or a growling sound. Pinion gear bearings have a constant-pitch noise. This noise changes only with vehicle speed. Pinion bearing noise will be higher because it rotates at a faster rate. Drive the vehicle and load the differential. If bearing noise occurs the pinion rear bearing is the source of the noise. If the bearing noise is heard during a coast, front bearing is the source. Worn, damaged differential bearings usually produce a low pitch noise. Differential bearing noise is similar to pinion bearing. The pitch of differential bearing noise is also constant and varies only with vehicle speed. Axle shaft bearings produce noise and vibration when worn or damaged. The noise generally changes when the bearings are loaded. Road test the vehicle. Turn the vehicle sharply to the left and to the right.


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REAR SUSPENSION AND AXLES

This will load the bearings and change the noise level. Where axle bearing damage is slight, the noise is usually not noticeable at speeds above 30 mph.

LOW SPEED KNOCK Low speed knock is generally caused by a worn U-joint or by worn side-gear thrust washers. A worn pinion gear shaft bore will also cause low speed knock.

VIBRATION Vibration at the rear of the vehicle is usually caused by a: • Damaged drive shaft • Missing drive shaft balance weight • Worn, out-of-balance wheels • Loose wheel lug nuts • Worn U-joint • Loose spring U-bolts • Loose/broken springs • Damaged axle shaft bearings • Loose pinion gear nut • Excessive pinion yoke run out • Bent axle shaft Check for loose or damaged front-end components or engine/transmission mounts. These components can contribute to what appears to be a rear-end vibration. Do not overlook engine accessories, brackets and drive belts. All driveline components should be examined before starting any repair. Refer to Group 22, Wheels and Tires for additional information.

DRIVELINE SNAP A snap or clunk noise when the vehicle is shifted into gear (or the clutch engaged), can be caused by: • High engine idle speed • Loose engine/transmission/transfer case mounts • Worn U-joints • Loose spring mounts • Loose pinion gear nut and yoke • Excessive ring gear backlash • Excessive side gear\ase clearance The source of a snap or a clunk noise can be determined with the assistance of a helper. Raise the vehicle on a hoist with the wheels free to rotate. Instruct the helper to shift the transmission into gear. Listen for the noise, a mechanics stethoscope is helpful in isolating the source of a noise.

REAR AXLE ALIGNMENT MEASUREMENT The following procedure can be used to determine if abnormal rear tire tread wear is the result of a bent or deformed rear axle shaft. (1) Raise both rear wheels off the surface with a frame contact hoist.

J (2) Attach a one-inch long piece of masking tape at the center of each tire tread for use as reference marks. (3) Rotate the rear wheels until both reference marks face the front of the vehicle. Measure the distance between the outside edges of the two pieces of tape. Record this measurement as the front of tire (FTR) measurement. (4) Rotate the rear wheels until both reference marks face the rear of the vehicle. Measure the distance between the outside edges of the two pieces of tape. Record this measurement as the rear of tire (RTR) measurement. (5) Subtract the (RTR) measurement from the (FTR) measurement to obtain the amount of wheel toe. The acceptable rear wheel toe-in position is 1/16 inch (1.6 mm) to 3/16 inch (4.8 mm) toe-out. (6) Rotate the rear wheels until the reference marks are facing downward. Measure the distance between the outside edges of the two pieces of tape. Record this measurement as the bottom of tire (BTR) measurement. (7) Average the (FTR) and the (RTR) distance measurements. Subtract the (BTR) measurement from this average distance to obtain the camber. The acceptable amount of camber is 1/16 inch to 3/32 inch (1.6 to 2.4 mm). (FTR + RTR) DIVIDED BY 2 (TWO) MINUS BTR EQUALS CAMBER If the (BTR) distance measurement is less than the average FTR and RTR distance measurement, the camber will be positive ( + ). If the (BTR) distance measurement is greater than the average FTR and RTR distance, the camber will be negative ( - ). If the toe position or camber is not acceptable, a bent or deformed rear axle shaft is most likely the cause.

LIMITED SLIP DIFFERENTIAL Under normal traction conditions, engine torque is divided evenly. With low-traction surfaces, engine torque is transferred to the wheel with the most tire traction. When diagnosing a limited-slip differential the wheel with the least traction can continue spinning. The most common problem is a chatter noise when turning corners. Check for incorrect or contaminated lubricant. Replace the gear lubricant if necessary. • With Trac-Lok™ differentials add a container of MOPAR Trac-Lok Lubricant. This will correct the condition in most instances. If the chatter persists, clutch damage could have occurred. After changing the lubricant, drive the vehicle and make 10 to 12 slow, figure-eight turns. This maneuver will pump lubricant through the clutches.


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REAR SUSPENSION AND AXLES SERVICE DIAGNOSIS

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REAR SUSPENSION AND AXLES SERVICE DIAGNOSIS (CONT’D)

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MODEL 35 AXLE INDEX page Axle Shaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . Axle Shaft Seal and Bearing . . . . . . . . . . . . . . Backlash and Contact Pattern Analysis . . . . . . Cleaning/Inspection . . . . . . . . . . . . . . . . . . . . . Differential Assembly . . . . . . . . . . . . . . . . . . . . Differential Disassembly . . . . . . . . . . . . . . . . . Differential Measurement and Installation . . . . . Differential Removal . . . . . . . . . . . . . . . . . . . . Drive Axle Assembly Replacement—XJ Vehicles

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16 17 27 20 21 18 25 18 14

GENERAL INFORMATION The Model 35 housing has an iron center casting (differential housing) with axle shaft tubes extending from either side. The tubes are pressed into and welded to the differential housing to form a one-piece axle housing. The integral type housing, hypoid gear design has the centerline of the pinion set below the centerline of the ring gear. The axle has a vent hose to relieve internal pressure caused by lubricant vaporization and internal expansion. The axles are equipped with semi-floating axle shafts, meaning that loads are supported by the axle shaft and bearings. The axle shafts are retained by C-clips in the differential side gears. The cover provides a means for servicing the differential without removing the axle. Axles may be equipped with drum or disc brakes. The axles that are equipped with ABS brake have a tone ring pressed on the axle shaft. Use care when removing axle shafts as NOT to damage the tone wheel or the sensor. The Model 35 axle has the assembly part number and gear ratio listed on a tag. The tag is attached to the housing cover. Build date identification codes are stamped on the axle shaft tube cover side. The differential case is a one-piece design. The differential pinion mate shaft is retained with a threaded roll pin. Differential bearing preload and ring gear backlash is adjusted by the use of spacer shims. Pinion bearing preload is set and maintained by the use of a collapsible spacer. For complete drive axle assembly removal and installation refer to Drive Axle Assembly Replacement in this Group.

LUBRICANT SPECIFICATIONS Multi-purpose, hypoid gear lubricant should be used for Model 35 axle. The lubricant should have

page Drive Axle Assembly Replacement—YJ Vehicles Final Assembly . . . . . . . . . . . . . . . . . . . . . . . . General Information . . . . . . . . . . . . . . . . . . . . Lubricant Change . . . . . . . . . . . . . . . . . . . . . . Lubricant Specifications . . . . . . . . . . . . . . . . . . Pinion Gear Depth Information . . . . . . . . . . . . Pinion Measurement and Assembly . . . . . . . . . Pinion Removal/Disassembly . . . . . . . . . . . . . . Pinion Shaft Seal Replacement . . . . . . . . . . . .

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14 29 13 13 13 21 22 19 15

MIL-L-2105C and API GL 5 quality specifications. MOPAR Hypoid Gear Lubricant conforms to both of these specifications. • Lubricant for Model 35 axle is a thermally stable SAE 80W-90 gear lubricant. • Lubricant for Model 35 axle with Trailer Tow is SAE 75W-140 SYNTHETIC gear lubricant. • Trac-Lok differentials add 4 oz. of friction modifier. • Lubricant quantity is 1.66 L (3.50 pts.). Refer to Group 0, Lubrication and Maintenance for additional information. CAUTION: If axle is submerged in water, lubricant must be replaced immediately to avoid possible premature axle failure.

LUBRICANT CHANGE The gear lubricant will drain quicker if the vehicle has been recently driven. (1) Raise and support the vehicle. (2) Remove the lubricant fill hole plug from the differential housing cover. (3) Remove the differential housing cover and drain the lubricant from the housing. (4) Clean the housing cavity with a flushing oil, light engine oil or lint free cloth. Do not use water, steam, kerosene or gasoline for cleaning. (5) Remove the sealant from the housing and cover surfaces. (6) Apply a bead of MOPARt Silicone Rubber Sealant to the housing cover (Fig. 1). Allow the sealant to cure for a few minutes. Install the housing cover within 5 minutes after applying the sealant. If not installed the sealant must be removed and another bead applied. (7) Install the cover and any identification tag. Tighten the cover bolts to 41 Nzm (30 ft. lbs.) torque. (8) Refill differential with Mopar Hypoid Gear Lubricant to bottom of the fill plug hole.


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REAR SUSPENSION AND AXLES

J (9) Support the axle with a hydraulic jack under the differential. (10) Remove the spring U-bolts from the plate brackets. (11) Lower the jack enough to remove the axle.

INSTALLATION CAUTION: Suspension components with rubber bushings should be tightened with the vehicle at normal height. It is important to have the springs supporting the weight of the vehicle when the fasteners are torqued. If springs are not at their normal ride position, vehicle ride comfort could be affected and premature bushing wear may occur. Rubber bushings must never be lubricated.

Fig. 1 Typical Housing Cover With Sealant CAUTION: Overfilling the differential can result in lubricant foaming and overheating. Trac-Lok Differentials; A container of Trac-Lok lubricant (friction modifier) should be added after repair service or a lubricant change. (9) Install the fill hole plug and lower the vehicle. LIMITED SLIP DIFFERENTIAL vehicles should be road tested by making 10 to 12 slow figure-eight turns. This maneuver will pump the lubricant through the clutch discs to eliminate a possible chatter noise complaint.

DRIVE AXLE ASSEMBLY REPLACEMENT—XJ VEHICLES REMOVAL (1) Raise the vehicle and position support stands under the frame rails slightly in front the springs. (2) Remove the rear wheels. (3) Mark the drive shaft yoke and axle pinion yoke for alignment reference. Disconnect the drive shaft from the axle. (4) Disconnect the axle vent hose. (5) Disconnect the parking brake cables at the equalizer or backing plate. (6) Disconnect the shock absorbers from the axle brackets. (7) Disconnect the brake hose at the axle junction block. Do not disconnect the wheel cylinder tubing fittings. (8) If equipped, disconnect ABS wiring connections at the axle.

(1) Support the axle on a hydraulic jack under the differential. Position the axle under the vehicle. (2) Raise the axle and align the spring center bolts with the locating holes in the axle pads and plate brackets. (3) Install the spring U-bolts through the plate brackets and tighten to 70 Nzm (52 ft. lbs.) torque. (4) Install ABS wiring connections (if equipped) at the axle. (5) Connect the brake hose at the axle junction block. (6) Install the shock absorbers to the axle brackets and tighten to 62 Nzm (46 ft. lbs.) torque. (7) Connect the parking brake cables at the equalizer or backing plate. (8) Connect the vent hose to the tube fitting. (9) Align the reference marks and connect the drive shaft to the axle yoke. Tighten the U-joint clamp bolts to 19 Nzm (14 ft. lbs.) torque. (10) Check differential lubricant and add if necessary. (11) Install the wheel and tire. (12) Bleed the brakes. (13) Remove the supports and lower the vehicle.

DRIVE AXLE ASSEMBLY REPLACEMENT—YJ VEHICLES REMOVAL (1) Raise the vehicle and position support stands under the frame rails slightly in front the springs. (2) Remove the rear wheels. (3) Mark the drive shaft yoke and axle pinion yoke for alignment reference. Disconnect the drive shaft from the axle. (4) Disconnect the axle vent hose. (5) Disconnect the parking brake cables at the equalizer or backing plate. (6) Disconnect the shock absorbers from the plate brackets.


J (7) Disconnect the brake hose at the axle junction block. Do not disconnect the wheel cylinder tubing fittings. (8) Disconnect the track bar at the axle bracket. (9) Support the axle with a hydraulic jack under the differential. Raise the axle just enough to relieve the axle weight from the springs. (10) Remove the spring U-bolts from the plate brackets. (11) Loosen BUT DO NOT REMOVE the bolts that attach the spring front pivot at the frame rail brackets. This will allow the springs to pivot without binding on the bushings. (12) Disconnect shackle from the springs and lower the springs to the surface. (13) Lower the jack enough to remove the axle.

INSTALLATION CAUTION: Suspension components with rubber bushings should be tightened with the vehicle at normal height. It is important to have the springs supporting the weight of the vehicle when the fasteners are torqued. If springs are not at their normal ride position, vehicle ride comfort could be affected and premature bushing wear may occur. Rubber bushings must never be lubricated. (1) Support the axle on a hydraulic jack under the differential. Position the axle under the vehicle. (2) Raise the springs and install the spring shackle bolts. Do not tighten at this time. (3) Lower the axle and align the spring center bolts with the locating holes in the axle pads and plate brackets. (4) Install the spring U-bolts through the plate brackets and tighten to 122 Nzm (90 ft. lbs.) torque. (5) Connect the track bar to the axle bracket and install the bolt. Do not tighten at this time. It is important that the springs support the weight of the vehicle when the track bar is connected. If the springs are not at their usual position, vehicle ride comfort could be affected. (6) Connect the brake hose at the axle junction block. (7) Install the shock absorbers to the axle brackets and tighten to 61 Nzm (45 ft. lbs.) torque. (8) Connect the parking brake cables at the equalizer or backing plate. (9) Connect the vent hose to the tube fitting. (10) Align the reference marks and connect the drive shaft to the axle yoke. Tighten the U-joint clamp bolts to 19 Nzm (14 ft. lbs.) torque. (11) Check differential lubricant and add if necessary. (12) Install the wheel and tire. (13) Bleed the brakes. (14) Remove the supports and lower the vehicle.

REAR SUSPENSION AND AXLES

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(15) Tighten the spring front pivot bolt/nut to 142 Nzm (105 ft. lbs.) torque. Tighten the spring shackle bolt/nut to 135 Nzm (100 ft. lbs.) torque. (16) Tighten the track bar bolt at the axle bracket to 142 Nzm (105 ft. lbs.) torque.

PINION SHAFT SEAL REPLACEMENT REMOVAL (1) Raise and support the vehicle. (2) Remove wheel and tire assemblies. (3) Mark the drive shaft yoke and pinion yoke for installation alignment reference. (4) Remove the drive shaft from the yoke. (5) Rotate the pinion gear three or four times. Make sure brakes are not dragging during this procedure. (6) Measure the amount of torque (in Newtonmeters or inch-pounds) necessary to rotate the pinion gear with a torque wrench. Note the torque for installation reference. It must be known to properly adjust the pinion gear bearing preload torque after seal installation. (7) Remove the pinion yoke nut and washer. Use Remover C-452 and Wrench C-3281 to remove the pinion yoke (Fig. 2). (8) Mark the positions of the yoke and pinion gear for installation alignment reference.

Fig. 2 Pinion Yoke Removal (9) Use Remover 7794A and slide hammer to remove the pinion gear seal (Fig. 3).

INSTALLATION (1) Apply a light coating of gear lubricant on the lip of pinion seal. Install seal with Installer D-163 and Handle C-4171 (Fig. 4). (2) Align the installation reference marks and install yoke on the pinion gear with Installer W-162-D. (3) Install a new nut on the pinion gear. Tighten the nut only enough to remove the shaft end play.


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REAR SUSPENSION AND AXLES

J

Fig. 3 Seal Removal

Fig. 5 Tightening Pinion Shaft Nut (7) Continue tightening the shaft nut in small increments until the correct bearing preload torque is attained. (8) Align the installation reference marks and attach the drive shaft to the yoke. (9) Add API grade GL 5 hypoid gear lubricant to the differential housing, if necessary. (10) Install wheel and tire assemblies. (10) Lower the vehicle.

AXLE SHAFT

Fig. 4 Pinion Seal Installation CAUTION: Exercise care during the bearing preload torque adjustment. Do not over-tighten, or loosen and then re-tighten the nut. Do not exceed the bearing preload torque. The collapsible preload spacer on the shaft will have to be replaced. The bearing preload torque will be re-adjusted afterward. (4) Install a socket and inch-pound torque wrench on the pinion nut. (5) Rotate the shaft with the torque wrench and note the torque. The required preload torque is equal to the amount recorded during removal plus an additional 0.56 Nzm (5 in. lbs.). (6) Use Flange Wrench C-3281 to retain the yoke and shaft (Fig. 5). Tighten the shaft nut in very small increments.

REMOVAL (1) Raise and support the vehicle. (2) Remove the wheel and tire. (3) Remove the brake drum. (4) Clean all the foreign material from housing cover area. (5) Loosen the housing cover bolts. Drain the lubricant from the housing and the axle shaft tubes. Remove the housing cover. (6) Rotate the differential case so that the pinion mate gear shaft lock screw is accessible. Remove the lock screw and the pinion mate gear shaft from the case (Fig. 6). (7) Force the axle shaft in toward the center of the vehicle. Remove the axle shaft C-clip lock from the axle shaft (Fig. 7). (8) Remove the axle shaft. Use care to prevent damage to the axle shaft bearing and seal, which will remain in the axle shaft tube. (9) Inspect axle shaft seal for leakage or damage.


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AXLE SHAFT SEAL AND BEARING REMOVAL (1) Remove the axle shaft. Refer to the Removal procedures in this Group. (2) Remove the axle shaft seal from the end of the axle shaft tube with a small pry bar. (3) Remove the bearing if it appears damaged. The seal and bearing can be removed at the same time with the bearing removal tool. (4) Remove the axle shaft bearing from the tube (Fig. 8) with Bearing Removal Tool Set 6310 (T.Ar 960-02).

Fig. 6 Mate Shaft Lock Screw

Fig. 7 Axle Shaft C-Clip Lock (10) Inspect the roller bearing contact surface on the axle shaft for signs of brinelling, spalling and pitting. (11) If any of these conditions exist, the axle shaft and bearing or seal must be replaced.

INSTALLATION (1) Lubricate the bearing bore and seal lip with gear lubricant. Insert the axle shaft through the seal, bearing, and engage it with the side gear splines. Use care to prevent the shaft splines from damaging the axle shaft seal lip. (2) Insert the C-clip lock in the end of the axle shaft. Push the axle shaft outward to seat the C-clip lock in the side gear. (3) Insert the mate shaft into the case and through the thrust washers and pinion gears. Align the hole in shaft with the hole in the differential case and install the lock screw with Loctitet on the threads. Tighten the screw to 19 Nzm (14 ft. lbs.) torque. (4) Install the cover and add fluid. Refer to the Drain and Refill in this section.

Fig. 8 Axle Shaft Bearing Removal Tool (5) Inspect the axle shaft tube bore for roughness and burrs. Remove as necessary. CAUTION: Inspect the housing bore for burrs. Remove them if they exist.

INSTALLATION Do not install the original axle shaft seal. Always install a new seal. (1) Wipe the bore in the axle shaft tube clean. (2) Install axle shaft bearing with Installer 6436 and Handle C-4171. Ensure part number on the bearing must go against the Installer. (3) Install the new axle shaft seal (Fig. 9) with Installer 6437 and Handle C-4171. (4) Install the Axle Shaft. Refer to the installation procedure.


3 - 18

REAR SUSPENSION AND AXLES

Fig. 9 Axle Shaft Seal Installation

DIFFERENTIAL REMOVAL To service the differential the axle shafts must be removed. Refer to the removal procedures in this Group. (1) Note the installation reference letters stamped on the bearing caps and housing machined sealing surface (Fig. 10).

J

Fig. 11 Spread Differential Housing (5) Separate the housing enough to remove the case from the housing. Measure the distance with the dial indicator (Fig. 11). (6) Remove the dial indicator. (7) Pry the differential case loose from the housing. To prevent damage, pivot on housing with the end of the pry bar against spreader (Fig. 12).

Fig. 10 Bearing Cap Identification (2) Remove the differential bearing caps. (3) Position Spreader W-129-B with the tool dowel pins seated in the locating holes (Fig. 11). Install the holddown clamps and tighten the tool turnbuckle finger-tight. (4) Install a pilot stud at the left side of the differential housing. Attach Dial Indicator to housing pilot stud. Load the indicator plunger against the opposite side of the housing (Fig. 11) and zero the indicator. CAUTION: Do not spread over 0.38 mm (0.015 in). If the housing is over-separated, it could be distorted or damaged.

Fig. 12 Differential Removal (8) Remove the case from housing. Mark or tag bearing cups and outboard shim/spacer (selected thickness) indicating which side they were removed. Remove spreader from housing.

DIFFERENTIAL DISASSEMBLY (1) Remove the bearings from the differential case with Press C-293-PA, Plug SP3289, Adapter C-293-18 (Fig. 13).


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1995 jeep cherokee, jeep wrangle service repair manual  
1995 jeep cherokee, jeep wrangle service repair manual  
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