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CHRYSLER CORPORATION SERVICE MANUAL and SUPPLEMENT 1996 JEEPT GRAND CHEROKEE 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 © 1995 Chrysler Corporation 15M0895

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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 system and 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.

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GROUP TAB LOCATOR PAGE NOTE: Groups with the suffix “-S� are Supplements to the original service manual publication.

IN 0 0-S 2 3 3-S 5 7 8A 8B 8C 8D 8E 8F 8G 8H 8J 8K 8L 8M 8N 8P 8Q 8R 8S 8T 8U 8V 8W 9 11 13 14 19 21 21-S 22 23 24 25

Introduction Lubrication and Maintenance Lubrication and Maintenance Suspension Differential and Driveline Differential and Driveline Brakes Cooling System Battery Starting Systems Charging System Ignition System Instrument Panel Systems Audio Systems Horn Systems Vehicle Speed Control System Turn Signal and Hazard Warning Systems Wiper and Washer Systems Lamps Passive Restraint Systems Electrically Heated Systems Power Lock Systems Vehicle Theft/Security Systems Power Seat Systems Power Window Systems Power Mirror Systems Chime/Buzzer Warning Systems Overhead Console Systems Wiring Diagrams Engine Exhaust System and Intake Manifold Frame and Bumpers Fuel System Steering Transmission and Transfer Case Transmission and Transfer Case Tires and Wheels Body Heating and Air Conditioning Emission Control Systems Component and System Index Supplement Component and System Index

Service Manual Comment Forms

(Rear of Manual)


INTRODUCTION

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INTRODUCTION CONTENTS page

GENERAL INFORMATION BODY CODE PLATE . . . . . . . . . . . . . . . . . . . . . . 2 FASTENER IDENTIFICATION . . . . . . . . . . . . . . . . 3 INTERNATIONAL VEHICLE CONTROL AND DISPLAY SYMBOLS . . . . . . . . . . . . . . . . . . . . 3 GENERAL INFORMATION VEHICLE IDENTIFICATION NUMBER (VIN) The Vehicle Identification Number (VIN) plate is attached to the top left side of the instrument panel. The VIN contains 17 characters that provide data concerning the vehicle. Refer to the decoding chart to

page

METRIC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . TORQUE REFERENCES . . . . . . . . . . . . . . . . . . . . VEHICLE DIMENSIONS . . . . . . . . . . . . . . . . . . . . VEHICLE IDENTIFICATION NUMBER (VIN) . . . . VEHICLE SAFETY CERTIFICATION LABEL . . . . .

determine the identification of a vehicle. The Vehicle Identification Number is also imprinted on the: • Body Code Plate. • Equipment Identification Plate. • Vehicle Safety Certification Label. • Frame rail.

VEHICLE IDENTIFICATION NUMBER DECODING CHART POSITION

3 4 3 1 2

INTERPRETATION

CODE = DESCRIPTION

1

Country of Origin

1 = United States

2

Make

J = Jeep

3

Vehicle Type

4 = MPV

4

Gross Vehicle Weight Rating

G = 5001-6000 lbs.

5

Vehicle Line

X = Grand Cherokee 4X2 (LHD) Z = Grand Cherokee 4X4 (LHD) W = Grand Cherokee 4X4 (RHD)

6

Series

5 = Laredo 6 = SE 7 = Limited

7

Body Style

8 = 4dr Sport Utility

8

Engine

S = 4.0 Liter Y = 5.2 Liter

9

Check Digit

10

Model Year

T = 1996

11

Assembly Plant

C = Jefferson Assembly

12 thru 17

Vehicle Build Sequence


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GENERAL INFORMATION (Continued)

VEHICLE SAFETY CERTIFICATION LABEL A vehicle safety certification label (Fig. 1) is attached to every Chrysler Corporation vehicle. The label certifies that the vehicle conforms to all applicable Federal Motor Vehicle Safety Standards. The label also lists: • Month and year of vehicle manufacture. • Gross Vehicle Weight Rating (GVWR). The gross front and rear axle weight ratings (GAWR’s) are based on a minimum rim size and maximum cold tire inflation pressure. • Vehicle Identification Number (VIN). • Type of vehicle. • Type of rear wheels. • Bar code. • Month, Day and Hour (MDH) of final assembly. • Paint and Trim codes. • Country of origin. The label is located on the driver-side door shutface.

Fig. 2 Body Code Plate The last nine positions of row 7 will contain a 2-digit code and a 6- digit serial number. The last code on a vehicle code plate will be followed by the imprinted word END. When two 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.

VEHICLE CODE DECODING

Fig. 1 Vehicle Safety Certification Label—Typical

BODY CODE PLATE A metal Body Code (Fig. 2) plate is attached (riveted) to the top, left side of the radiator reinforcement. There can be a maximum of seven rows of information on the plate. The information should be read from left to right. Start with line 1 at the bottom of the plate up to line 7 at the top of the code plate. Refer to the decoding chart to decode lines 1 through 3. Lines 4 through 7 on the plate are imprinted in sequence according to the following descriptions: • 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: • The unused space will remain blank. • The code will be listed in the next row.


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GENERAL INFORMATION (Continued)

Vehicle Dimensions

VEHICLE DIMENSIONS The Vehicle Dimensions chart provides the dimensions for each type of Grand Cherokee vehicle.

INTERNATIONAL VEHICLE CONTROL AND DISPLAY SYMBOLS The graphic symbols illustrated in the following chart are used to identify various instrument controls. The symbols correspond to the controls and displays that are located on the instrument panel.

FASTENER IDENTIFICATION THREAD IDENTIFICATION SAE and metric bolt/nut threads are not the same. The difference is described in the Thread Notation chart (Fig. 3). 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, the greater the bolt strength. Some metric nuts are imprinted with a single-digit strength class on the nut face. Refer to the Fastener Identification and Fastener Strength Charts.

METRIC SYSTEM WARNING: USE OF AN INCORRECT FASTENER MAY RESULT IN COMPONENT DAMAGE OR PERSONAL INJURY. Figure art, specifications and torque references in this Service Manual are identified in metric and SAE format. During any maintenance or repair procedures, it is important to salvage metric fasteners (nuts, bolts, etc.) for reassembly. If the fastener is not salvageable, a fastener of equivalent specification should be used. The metric system is based on quantities of one, ten, one hundred, one thousand and one million (Fig. 4). The following chart will assist in converting metric units to equivalent English and SAE units, or vise versa. Refer to the Conversion Chart to convert torque values listed in metric Newton- meters (N¡m). Also,


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GENERAL INFORMATION (Continued) INTERNATIONAL CONTROL AND DISPLAY SYMBOLS

TORQUE REFERENCES Individual Torque Charts appear at the end of many Groups. Refer to the Standard Torque Specifications Chart for torque references not listed in the individual torque charts.

Fig. 3 Thread Notation—SAE and Metric use the chart to convert between millimeters (mm) and inches (in.)


INTRODUCTION

ZJ GENERAL INFORMATION (Continued) FASTENER IDENTIFICATION

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6

INTRODUCTION

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GENERAL INFORMATION (Continued) FASTENER STRENGTH


INTRODUCTION

ZJ GENERAL INFORMATION (Continued)

Fig. 4 Metric Prefixes CONVERSION FORMULAS AND EQUIVALENT VALUES

7


8

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GENERAL INFORMATION (Continued) METRIC CONVERSION


INTRODUCTION

ZJ GENERAL INFORMATION (Continued) TORQUE SPECIFICATIONS

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LUBRICATION AND MAINTENANCE

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GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . 1 JUMP STARTING, HOISTING AND TOWING . . . . 8

MAINTENANCE SCHEDULES . . . . . . . . . . . . . . . . 3

GENERAL INFORMATION INDEX page

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GENERAL INFORMATION CLASSIFICATION OF LUBRICANTS . . . . . . . . . . . 1 FLUID CAPACITIES . . . . . . . . . . . . . . . . . . . . . . . 2 INTERNATIONAL SYMBOLS . . . . . . . . . . . . . . . . 1

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . 1 PARTS AND LUBRICANT RECOMMENDATIONS ........................................ 1

GENERAL INFORMATION

INTERNATIONAL SYMBOLS

INTRODUCTION

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

Service and maintenance procedures for components and systems listed in Schedule—A or B can be found by using the Group Tab Locator index at the front of this manual. If it is not clear which group contains the information needed, refer to the index at the back of this manual. There are two maintenance schedules that show proper service based on the conditions that the vehicle is subjected to. Schedule—A, lists scheduled maintenance to be performed when the vehicle is used for general transportation. Schedule—B, lists maintenance intervals for vehicles that are operated under the conditions listed at the beginning of the Maintenance Schedule section. Use the schedule that best describes your driving conditions. Where time and mileage are listed, follow the interval that occurs first.

PARTS AND LUBRICANT RECOMMENDATIONS When service is required, Chrysler Corporation recommends that only Mopart brand parts, lubricants and chemicals be used. Mopar provides the best engineered products for servicing Chrysler Corporation vehicles.

Fig. 1 International Symbols

CLASSIFICATION OF LUBRICANTS Only lubricants that are endorsed by the following organization should be used to service a Chrysler Corporation vehicle. • Society of Automotive Engineers (SAE) • American Petroleum Institute (API) (Fig. 2) • National Lubricating Grease Institute (NLGI) (Fig. 3)


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GENERAL INFORMATION (Continued)

Fig. 3 NLGI Symbol Fig. 2 API Symbol ENGINE OIL SAE GRADE RATING INDICATES ENGINE OIL VISCOSITY 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. • SAE 30 = single grade engine oil. • SAE 10W-30 = multiple grade engine oil. API QUALITY CLASSIFICATION 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 engine oil that is API Service Grade Certified or an oil that conforms to the API Service Grade SH or SH/CD. MOPAR engine oils conform to all of these service grades. Refer to Group 9, Engine for engine oil specification. GEAR LUBRICANTS SAE ratings also apply to multiple grade gear lubricants. In addition, API classification defines the lubricants usage. LUBRICANTS AND GREASES Lubricating grease is rated for quality and usage by the NLGI. All approved products have the NLGI symbol (Fig. 3) on the label. At the bottom NLGI symbol is the usage and quality identification letters. Wheel bearing lubricant is identified by the letter “G”. Chassis lubricant is identified by the latter “L”. The letter following the usage letter indicates the quality of the lubricant. The following symbols indicate the highest quality.

FLUID CAPACITIES FUEL TANK All. . . . . . . . . . . . . . . . . . . . . . . . . . . .87.4 L (23 gal.)

ENGINE OIL W/FILTER CHANGE 4.0L . . . . . . . . . . . . . . . . . . . . . . . . . . .5.7 L (6.0 qts.) 5.2L . . . . . . . . . . . . . . . . . . . . . . . . . . .4.7 L (5.0 qts.)

COOLING SYSTEM 4.0L . . . . . . . . . . . . . . . . . . . . . . . .11.4 L (12.0 qts.)* 5.2L . . . . . . . . . . . . . . . . . . . . . . . .14.1 L (14.9 qts.)* *Includes 2.2 L (2.3 qts.) for coolant recovery bottle.

AUTOMATIC TRANSMISSION Dry fill capacity.* 42RE . . . . . . . . . . . . . . . . . . . .8.0-10.4 L (17-22 pts.) 44RE . . . . . . . . . . . . . . . . . . . .8.0-10.4 L (17-22 pts.) *Depending on type and size of internal cooler, length and inside diameter of cooler lines, or use of an auxiliary cooler, these figures may vary. Refer to Group 21, Transmission for proper fluid fill procedure.

FRONT AXLE Model 30 . . . . . . . . . . . . . . . . . . . . .1.48 L (3.13 pts.)

REAR AXLE Model 44* . . . . . . . . . . . . . . . . . . . .2.24 L (4.75 pts.) *If the vehicle is equipped with TRAC-LOK, include 0.11 L (0.25 pts.) of friction modifier. NOTE: Vehicles with trailer tow, must use a synthetic lubricant. Refer to Group 3, Differential and Driveline for service procedures.


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MAINTENANCE SCHEDULES INDEX page

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GENERAL INFORMATION INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . 3 SCHEDULE—A . . . . . . . . . . . . . . . . . . . . . . . . . . 3

SCHEDULE—B . . . . . . . . . . . . . . . . . . . . . . . . . . 5 UNSCHEDULED INSPECTION . . . . . . . . . . . . . . . 3

GENERAL INFORMATION INTRODUCTION There are two maintenance schedules that show proper service intervals for ZJ 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 trips driving less than 5 miles (8 km) • Frequent driving in dusty conditions • Frequent trailer towing • Extensive idling • More than 50% of your driving is at sustained high speeds during hot weather, above 90°F (32°C) • Off road driving • Desert operation

EMISSION CONTROL SYSTEM MAINTENANCE The scheduled emission maintenance listed in bold type on the Maintenance 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.

UNSCHEDULED INSPECTION AT EACH STOP FOR FUEL • Check engine oil level, add as required. • Check windshield washer solvent and add if required. ONCE A MONTH • Check tire pressure and look for unusual wear or damage.

• Inspect battery and clean and tighten terminals as required. Check electrolyte level and add water as needed. • Check fluid levels of coolant reservoir, power steering and transmission and add as needed. • Check all lights and all other electrical items for correct operation.

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 coolant level, hoses and clamps. • Lubricate suspension ball joints. • After completion of off-road (4WD) operation, the underside of the vehicle should be thoroughly inspected. Examine threaded fasteners for looseness.

SCHEDULE—A 7,500 miles (12 000 km) or at 6 months • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 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 only). • Inspect brake linings. 30,000 Miles (48 000 km) or at 24 months • Change engine oil. • Replace engine oil filter. • Replace engine air cleaner element. • Replace spark plugs. • Inspect drive belt. • Lubricate steering linkage.


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GENERAL INFORMATION (Continued) • Drain and refill automatic transmission fluid. • Drain and refill transfer case fluid.

37,500 Miles (60 000 km) or at 30 months • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 45,000 Miles (72 000 km) or at 36 months • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage. • Inspect brake linings. • Flush and replace engine coolant at 36 months, regardless of mileage. 52,500 Miles (84 000 km) or at 42 months • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). • Flush and replace engine coolant if not done at 36 months. 60,000 Miles (96 000 km) or at 48 months • Change engine oil. • Replace engine oil filter. • Replace engine air cleaner element. • Replace ignition wires. • Replace spark plugs. • Inspect PCV valve and replace if necessary (5.2L only).* • Inspect drive belt. • Lubricate steering linkage. • Drain and refill automatic transmission fluid. • Drain and refill transfer case fluid. • Replace fuel filter.** *This maintenance is recommended, but is not required to maintain warranty on the PCV valve. **Recommended for proper vehicle performance for vehicles built for sale in California. 67,500 Miles (108 000 km) or at 54 months • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). • Inspect brake linings 75,000 Miles (120 000 km) or at 60 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.

82,500 Miles (132 000 km) or at 66 months • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). • Flush and replace engine coolant if it has been 30,000 miles (48 000 km) or 24 months since last change. 90,000 Miles (144 000 km) or at 72 months • Change engine oil. • Replace engine oil filter. • Replace engine air cleaner element. • Replace spark plugs. • Inspect drive belt. • Lubricate steering linkage. • Drain and refill automatic transmission fluid. • Drain and refill transfer case fluid. • Inspect brake linings. 97,500 Miles (156 000 km) or at 78 months • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 105,000 Miles (168 000 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 (180 000 km) or at 90 months • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). • Inspect brake linings. • Flush and replace engine coolant if it has been 30,000 miles (48 000 km) or 24 months since last change. 120,000 Miles (192 000 km) or at 96 months • Change engine oil. • Replace engine oil filter. • Replace engine air cleaner element. • Replace ignition wires. • Replace spark plugs. • Inspect PCV valve and replace if necessary (5.2L only).* • Inspect drive belt. • Lubricate steering linkage. • Drain and refill automatic transmission fluid. • Drain and refill transfer case fluid. • Replace fuel filter.** *This maintenance is recommended, but is not required to maintain warranty on the PCV valve.


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GENERAL INFORMATION (Continued) **Recommended for proper vehicle performance for vehicles built for sale in California. IMPORTANT: Inspection and service should also be performed anytime a malfunction is observed or suspected.

SCHEDULE—B 3,000 Miles (5 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 6,000 Miles (10 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 9,000 Miles (14 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 12,000 Miles (19 000 km) • Change engine oil. • Replace engine oil filter. • Drain and refill automatic transmission fluid. • Drain and refill front and rear axles. • Lubricate steering linkage (4x4 only). • Inspect brake linings. 15,000 miles (24 000 km) • Change engine oil. • Replace engine oil filter. • Inspect engine air cleaner element, replace as necessary. • Lubricate steering linkage. 18,000 Miles (29 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 21,000 Miles (34 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 24,000 Miles (38 000 km) • Change engine oil. • Replace engine oil filter. • Drain and refill automatic transmission fluid. • Drain and refill front and rear axles. • Lubricate steering linkage (4x4 only). • Inspect brake linings.

27,000 Miles (43 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 30,000 Miles (48 000 km) • Change engine oil. • Replace engine oil filter. • Replace engine air cleaner element. • Inspect PCV valve and replace if necessary (5.2L only).* • Replace spark plugs. • Inspect drive belt. • Drain and refill transfer case fluid. • Lubricate steering linkage. *This maintenance is recommended to the customer, but is not required to maintain warranty on the PCV valve. 33,000 Miles (53 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 36,000 Miles (58 000 km) • Change engine oil. • Replace engine oil filter. • Drain and refill automatic transmission fluid. • Drain and refill front and rear axles. • Lubricate steering linkage (4x4 only). • Inspect brake linings. 39,000 Miles (62 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 42,000 Miles (67 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 45,000 Miles (72 000 km) • Change engine oil. • Replace engine oil filter. • Inspect engine air cleaner element, replace as necessary. • Lubricate steering linkage. 48,000 Miles (77 000 km) • Change engine oil. • Replace engine oil filter. • Drain and refill automatic transmission fluid. • Drain and refill front and rear axles. • Lubricate steering linkage (4x4 only). • Inspect brake linings.


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GENERAL INFORMATION (Continued) 51,000 Miles (82 000 km) • Change engine oil. • Replace engine oil filter. • Flush and replace engine coolant. • Lubricate steering linkage (4x4 only). 54,000 Miles (86 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 57,000 Miles (91 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 60,000 Miles (96 000 km) • Change engine oil. • Replace engine oil filter. • Replace engine air cleaner element. • Replace ignition wires. • Inspect PCV valve and replace if necessary (5.2L only).* • Replace spark plugs. • Inspect drive belt. • Drain and refill automatic transmission fluid. • Drain and refill transfer case fluid. • Drain and refill front and rear axles. • Lubricate steering linkage. • Replace fuel filter.** • Inspect brake linings. *This maintenance is recommended, but is not required to maintain warranty on the PCV valve. **Recommended for proper vehicle performance for vehicles built for sale in California.

• Inspect brake linings.

75,000 Miles (120 000 km) • Change engine oil. • Replace engine oil filter. • Inspect engine air cleaner element, replace as necessary. • Lubricate steering linkage. 78,000 Miles (125 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only). 81,000 Miles (130 000 km) • Change engine oil. • Replace engine oil filter. • Flush and replace engine coolant. • Lubricate steering linkage (4x4 only). 84,000 miles (134 000 km) • Change engine oil. • Replace engine oil filter. • Drain and refill automatic transmission fluid. • Drain and refill front and rear axles. • Lubricate steering linkage (4x4 only). • Inspect brake linings. 87,000 Miles (139 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only).

66,000 Miles (106 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only).

90,000 Miles (144 000 km) • Change engine oil. • Replace engine oil filter. • Replace engine air cleaner element. • Inspect PCV valve and replace if necessary (5.2L only).* • Replace spark plugs. • Inspect drive belt. • Drain and refill transfer case fluid. • Lubricate steering linkage. *This maintenance is recommended, but is not required to maintain warranty on the PCV valve.

69,000 Miles (110 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only).

93,000 Miles (149 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only).

72,000 Miles (115 000 km) • Change engine oil. • Replace engine oil filter. • Drain and refill automatic transmission fluid. • Drain and refill front and rear axles. • Lubricate steering linkage (4x4 only).

96,000 Miles (154 000 km) • Change engine oil. • Replace engine oil filter. • Drain and refill automatic transmission fluid. • Drain and refill front and rear axles. • Lubricate steering linkage (4x4 only).

63,000 Miles (101 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only).


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GENERAL INFORMATION (Continued) • Inspect brake linings.

• Lubricate steering linkage (4x4 only).

99,000 Miles (158 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only).

117,000 Miles (187 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only).

102,000 Miles (163 000 km) • Change engine oil. • Replace engine oil filter. • Lubricate steering linkage (4x4 only).

120,000 Miles (192 000 km) • Change engine oil. • Replace engine oil filter. • Replace engine air cleaner element. • Replace ignition wires. • Replace spark plugs. • Inspect PCV valve and replace if necessary (5.2L only). • Inspect drive belt. • Drain and refill automatic transmission fluid. • Drain and refill transfer case fluid. • Drain and refill front and rear axles. • Lubricate steering linkage. • Replace fuel filter.** • Inspect brake linings. *This maintenance is recommended, but is not required to maintain warranty on the PCV valve. **Recommended for proper vehicle performance for vehicles built for sale in California. IMPORTANT: Inspection and service should also be performed anytime a malfunction is observed or suspected.

105,000 Miles (168 000 km) • Change engine oil. • Replace engine oil filter. • Inspect engine air cleaner element, replace as necessary. • Lubricate steering linkage. 108,000 Miles (173 000 km) • Change engine oil. • Replace engine oil filter. • Drain and refill automatic transmission fluid. • Drain and refill front and rear axles. • Lubricate steering linkage (4x4 only). • Inspect brake linings. 111,000 Miles (178 000 km) • Change engine oil. • Replace engine oil filter. • Flush and replace engine coolant. • Lubricate steering linkage (4x4 only). 114,000 Miles (182 000 km) • Change engine oil. • Replace engine oil filter.


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JUMP STARTING, HOISTING AND TOWING INDEX page

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SERVICE PROCEDURES EMERGENCY TOW HOOKS . . . . . . . . . . . . . . . . 10 FOUR-WHEEL-DRIVE VEHICLE TOWING . . . . . 10 HOISTING RECOMMENDATIONS . . . . . . . . . . . 10

JUMP STARTING PROCEDURE . . . . . . . . . . . . . . 8 TOWING RECOMMENDATIONS . . . . . . . . . . . . . . 9 TWO-WHEEL-DRIVE VEHICLE TOWING . . . . . . . 9

SERVICE PROCEDURES JUMP STARTING PROCEDURE 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 BATTERY INDICATOR DOT IS YELLOW OR BRIGHT COLOR. BATTERY CAN EXPLODE. 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 ARCHING OF BATTERY CURRENT. WHEN USING A HIGH OUTPUT BOOSTING DEVICE, DO NOT ALLOW DISABLED VEHICLE’S BATTERY TO EXCEED 16 VOLTS. PERSONAL INJURY OR DAMAGE TO ELECTRICAL SYSTEM CAN RESULT.

(2) When using another vehicle as a booster source, turn off all accessories, place gear selector in park or neutral, set park brake or equivalent and operate engine at 1200 rpm. (3) On disabled vehicle, place gear selector in park or neutral and set park brake or equivalent. 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 (Fig. 1). Review all warnings in this procedure. (5) On disabled vehicle, connect RED jumper cable clamp to battery positive (+) terminal. Connect BLACK jumper cable clamp to the engine as close to the ground cable connection as possible (Fig. 1). 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 to charge to at least 12.4 volts (75% charge) before attempting to start engine. If engine does not start within 15 seconds, stop cranking engine and allow starter to cool (15 min.), before cranking again.

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: • Generator drive belt condition and tension. • Fuel fumes or leakage, correct if necessary. • Frozen battery. • Yellow or bright color test indicator, if equipped. • Low battery fluid level. CAUTION: If the cause of starting problem on disabled vehicle is severe, damage to booster vehicle charging system can result.

Fig. 1 Jumper Cable Clamp Connections


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LUBRICATION AND MAINTENANCE

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SERVICE PROCEDURES (Continued) 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.

TOWING RECOMMENDATIONS A vehicle equipped with SAE approved sling-type towing equipment or a wheel-lift towing device can be used to tow all ZJ vehicles. When towing a 4WD vehicle, use tow dollies under the opposite end of the vehicle. A vehicle with a flat-bed device can also be used to transport a disabled vehicle (Fig. 2).

• 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 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.

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 Chrysler Corporation recommends that a vehicle be towed with the rear end lifted, whenever possible.

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

Fig. 2 Tow Vehicles With Approved Equipment. SAFETY PRECAUTIONS The following safety precautions must be observed when towing a vehicle: • 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. • Do not allow passengers to ride in a vehicle being towed. • Always observe state and local laws regarding towing regulations.

Vehicles can be towed with the front wheels on the ground for extended distances at speeds not exceeding 48 km/h (30 mph). (1) Attach the J-hooks around the axle shaft tube outboard of the rear springs. (2) Position and center the sling under and forward of the rear bumper. (3) Attach safety chains (with pads) at each end of the rear bumper. (4) Turn the ignition switch to the OFF position to unlock the steering wheel. (5) Secure the steering wheel in 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.

TOWING-FRONT END LIFTED To prevent damage to front facia components, use only a Wheel-Lift type towing device or Flat-Bed hauling equipment.


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SERVICE PROCEDURES (Continued) 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.

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.

4WD TOWING-REAR END LIFTED (1) Raise the front of the vehicle off the ground and install tow dollies under front wheels. (2) Attach the J-hooks around the axle shaft tube outboard of the rear springs. (3) Position and center the sling under and forward of the rear bumper. (4) Attach safety chains (with pads) at each end of the rear bumper. (5) Turn the ignition switch to the OFF position to unlock the steering wheel. (6) Secure the steering wheel in straight ahead position with a clamp device designed for towing. (7) Shift the transfer case to NEUTRAL. 4WD TOWING-FRONT END LIFTED To prevent damage to front facia components, use only a Wheel-Lift type towing device or Flat-Bed hauling equipment. If using the wheel-lift towing method, install tow dollies under rear wheels.

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 emergency tow hooks. The tow hooks should be used for EMERGENCY purposes only. CAUTION: DO NOT use emergency tow hooks for tow truck hook-up or highway towing.

HOISTING RECOMMENDATIONS FLOOR JACK When properly positioned, a floor jack can be used to lift a ZJ vehicle (Fig. 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 vehicle with a floor jack positioned under: 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.

HOIST A vehicle can be lifted with: • A single-post, frame-contact hoist. • A twin-post, chassis hoist. • A ramp-type, drive-on hoist.


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LUBRICATION AND MAINTENANCE

SERVICE PROCEDURES (Continued) NOTE: When a frame-contact type hoist is used, verify that the lifting pads are positioned properly (Fig. 3). 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.

Fig. 3 Correct Vehicle Lifting Locations

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LUBRICATION AND MAINTENANCE CONTENTS page

GENERAL INFORMATION FLUID CAPACITIES . . . . . . . . . . . . . . . . . . . . . . . 1

FLUID CAPACITIES

an auxiliary cooler, these figures may vary. Refer to Group 21, Transmission for proper fluid fill procedure.

FUEL TANK

TRANSFER CASE

All. . . . . . . . . . . . . . . . . . . . . . . . . . . .87.4 L (23 gal.)

242 NVG . . . . . . . . . . . . . . . . . . . . . . .1.4 L (3.0 pts.) 249 NVG . . . . . . . . . . . . . . . . . . . . . . .1.1 L (2.5 pts.)

GENERAL INFORMATION

ENGINE OIL W/FILTER CHANGE FRONT AXLE 4.0L . . . . . . . . . . . . . . . . . . . . . . . . . . .5.7 L (6.0 qts.) 5.2L . . . . . . . . . . . . . . . . . . . . . . . . . . .4.7 L (5.0 qts.)

Model 30 . . . . . . . . . . . . . . . . . . . . . .1.18 L (2.5 pts.)

COOLING SYSTEM

REAR AXLE

4.0L . . . . . . . . . . . . . . . . . . . . . . . .11.4 L (12.0 qts.)* 5.2L . . . . . . . . . . . . . . . . . . . . . . . .14.1 L (14.9 qts.)* *Includes 2.2 L (2.3 qts.) for coolant recovery bottle.

Model 35* . . . . . . . . . . . . . . . . . . . . . .1.6 L (3.5 pts.) Model 44* . . . . . . . . . . . . . . . . . . . .2.24 L (4.75 pts.) *If the vehicle is equipped with Trac-lok, include 0.11 L (0.25 pts.) of friction modifier.

AUTOMATIC TRANSMISSION Dry fill capacity.*

NOTE: Vehicles with trailer tow, must use a synthetic lubricant. Refer to Group 3, Differential and Driveline for service procedures.

42RE . . . . . . . . . . . . . . . . . . . .8.0-10.4 L (17-22 pts.) 44RE . . . . . . . . . . . . . . . . . . . .8.0-10.4 L (17-22 pts.) *Depending on type and size of internal cooler, length and inside diameter of cooler lines, or use of


SUSPENSION

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SUSPENSION CONTENTS page

page

ALIGNMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 FRONT SUSPENSION . . . . . . . . . . . . . . . . . . . . . . 6

REAR SUSPENSION . . . . . . . . . . . . . . . . . . . . . . 13

ALIGNMENT INDEX page

page

GENERAL INFORMATION WHEEL ALIGNMENT . . . . . . . . . . . . . . . . . . . . . . 1 SERVICE PROCEDURES ALIGNMENT MEASUREMENTS AND

ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . 4 PRE-ALIGNMENT INSPECTION . . . . . . . . . . . . . . 1 SPECIFICATIONS Alignment Specifications . . . . . . . . . . . . . . . . . . . . 5

GENERAL INFORMATION

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. Incorrect wheel toe position is the most common cause of unstable steering and uneven 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. 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.

WHEEL ALIGNMENT 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. NOTE: 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 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. • 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. The angle is not

WARNING: Do not attempt to modify any suspension or steering component by heating and bending.

SERVICE PROCEDURES PRE-ALIGNMENT INSPECTION Before starting wheel alignment, the following inspection and necessary corrections must be completed. Refer to Suspension and Steering System Diagnosis Chart for additional information.


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SERVICE PROCEDURES (Continued)

Wheel Alignment Measurements (1) Tires with the same recommended air pressure, size, and tread wear. Refer to Group 22, Wheels and Tires for diagnosis information. (2) Inspect front wheel bearings for wear or adjustment. (3) Inspect front wheels for excessive radial, lateral runout and unbalance. Refer to Group 22, Wheels and Tires for diagnosis information.

(4) Inspect ball studs, linkage pivot points and steering gear for looseness, roughness, binding or a sticking condition. Refer to Group 19, Steering for additional information. (5) Inspect suspension components for wear and noise. Check components for correct torque.


SUSPENSION

ZJ SERVICE PROCEDURES (Continued) SUSPENSION AND STEERING SYSTEM DIAGNOSIS

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SUSPENSION

SERVICE PROCEDURES (Continued)

ZJ 1996 Grand Cherokee Publication No. 81-370-6147 TSB 26-04-96 April, 1996

Fig. 2 Drag Link and Tie Rod Clamp

Fig. 1 Cam Adjuster

TOE POSITION The toe position adjustment should be the last adjustment made. NOTE: The engine must remain running during the entire toe position adjustment. (1) Apply parking brakes. (2) Start the engine and turn wheels both ways before straightening the steering wheel. Center and secure the steering wheel. (3) Loosen the adjustment sleeve clamp bolts (Fig. 2). (4) Adjust the right wheel toe position with the drag link (Fig. 3) and (Fig. 4). Turn the sleeve until the right wheel is at the correct positive TOE-IN position. Position the clamp bolts as shown (Fig. 2) and tighten to 49Nzm (36 ft. lbs.).

Fig. 3 Steering Linkage—6 Cylinder Engine

NOTE: Tighten clamp bolt nearest the pitman arm first. Make sure the toe setting does not change during clamp tightening. (5) Adjust the left wheel toe position with the tie rod. Turn the sleeve until the left wheel is within .05° TOE-IN position as the right wheel. Position the clamp bolts as shown (Fig. 2) and tighten to: • Vehicles with 6 cyl engine: 27 Nzm (20 ft. lbs.) • Vehicles with 8 cyl engine: 49 Nzm (36 ft. lbs.)

Fig. 4 Steering Linkage—8 Cylinder Engine


SUSPENSION

ZJ SERVICE PROCEDURES (Continued) NOTE: Tighten the clamp bolt furthest from the wheel first. Make sure the toe setting does not change during clamp tightening. (6) Verify alignment specifications, then turn the engine off.

SPECIFICATIONS ALIGNMENT FRONT WHEELS ADJUSTMENT

PREFERRED

RANGE

CASTER

6.5° to 7.5°

CAMBER (not adjustable)

NA

-1.13° to + 0.13°

TOE-IN (each wheel)

0.12°

0° to + 0.22°

Toe Differential Left to Right .05°

1996 Grand Cherokee Publication No. 81-370-6147 TSB 26-04-96 April, 1996

REAR AXLE ADJUSTMENT

SPECIFICATION

THRUST ANGLE (not adjustable)

± .25°

TOTAL TOE-IN (not adjustable)

0.00 to + 0.5°

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FRONT SUSPENSION INDEX page

page

DESCRIPTION AND OPERATION FRONT SUSPENSION . . . . . . . . . . . . . . . . . . . . . 6 DIAGNOSIS AND TESTING SHOCK DIAGNOSIS . . . . . . . . . . . . . . . . . . . . . . 7 REMOVAL AND INSTALLATION AXLE BUSHING . . . . . . . . . . . . . . . . . . . . . . . . . . 9 COIL SPRING . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 HUB BEARING . . . . . . . . . . . . . . . . . . . . . . . . . . 10 LOWER SUSPENSION ARM . . . . . . . . . . . . . . . . 8 SHOCK ABSORBER . . . . . . . . . . . . . . . . . . . . . . . 7

STABILIZER BAR . . . . . . . . . . . . . . . . . . . . . . . . . 9 STEERING KNUCKLE . . . . . . . . . . . . . . . . . . . . . 8 TRACK BAR . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 UPPER SUSPENSION ARM . . . . . . . . . . . . . . . . . 9 WHEEL MOUNTING STUDS . . . . . . . . . . . . . . . . 11 SPECIFICATIONS TORQUE CHART . . . . . . . . . . . . . . . . . . . . . . . . 11 SPECIAL TOOLS FRONT SUSPENSION . . . . . . . . . . . . . . . . . . . . 12

DESCRIPTION AND OPERATION

• Coil springs • Dual-action shock absorbers • Jounce bumpers Link/Coil Suspension: The link/coil suspension allows each wheel to adapt to different road surfaces without greatly affecting 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

FRONT SUSPENSION The Grand Cherokee front suspension is a link/coil design comprised of (Fig. 1); • Drive axle (4WD), tube axle (2WD) • Track bar • Stabilizer bar • Upper and lower suspension arms

Fig. 1 Front Suspension


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DESCRIPTION AND OPERATION (Continued) replaceable ball studs attached to the axle tube yokes. Shock Absorbers: The shock absorbers dampen jounce and rebound motion 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 brackets. Coil Springs: The coil springs control ride quality and maintain proper ride height. The coil springs mount up in the wheelhouse which is part of the unitized body bracket. A rubber doughnut isolator is located between the top of the spring and the body. The bottom of the spring seats on a axle pad and is retained with a clip. Upper And Lower Suspension: The suspension arms use bushings to isolate road noise. The suspension arms are bolted to the frame and axle through the rubber bushings. The lower suspension arm uses cam bolts at the axle to allow for caster and pinion angle adjustment. The suspension arm travel is limited through the use of jounce bumpers in compression and shocks absorbers in rebound. Stabilizer Bar: The stabilizer bar is used to control 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 frame rails. Links are connected from the bar to the axle brackets. Track Bar: The track bar is used to control front axle lateral movement. The bar is attached to a frame rail bracket with a ball stud and isolated with a bushing at the axle bracket.

usually be stopped by tightening the attaching nuts. If the noise persists, inspect for damaged and worn bushings, and attaching components. Repair as necessary if any of these conditions exist. 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 in and out of the cylinder four or five times. The action throughout each stroke should be smooth and even. The shock absorber bushings do not require any type of lubrication. Do not attempt to stop bushing noise by lubricating them. Grease and mineral oilbase lubricants will deteriorate the bushing rubber.

REMOVAL AND INSTALLATION SHOCK ABSORBER REMOVAL (1) Remove the nut, retainer and grommet from the upper stud in the engine compartment (Fig. 2).

NOTE: Periodic lubrication of the front suspension (steering) system components is required. Refer to Group 0, Lubrication And Maintenance for the recommended maintenance schedule. 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.

DIAGNOSIS AND TESTING Fig. 2 Coil Spring & Shock Absorber

SHOCK DIAGNOSIS A noise from a shock absorber may be caused by movement between mounting bushings and metal brackets or attaching components. This noise can

(2) Remove the lower nuts and bolts from the axle bracket. Remove the shock absorber.


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REMOVAL AND INSTALLATION (Continued) 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 28 N·m (250 in. lbs.). (3) Install the upper grommet and retainer on the stud in the engine compartment. Install the nut and tighten to 23 N·m (17 ft. lbs.).

LOWER SUSPENSION ARM REMOVAL (1) Raise and support the vehicle. (2) Paint or scribe alignment marks on the cam adjusters and suspension arm for installation reference (Fig. 3).

COIL SPRING REMOVAL (1) Raise and support the vehicle. Position a hydraulic jack under the axle to support it. (2) Paint or scribe alignment marks on the cam adjusters and axle bracket for installation reference. (3) Mark and disconnect the front propeller shaft from the axle. (4) Remove the lower suspension arm nut, cam and cam bolt from the axle. (5) Disconnect the stabilizer bar link and shock absorber from the axle. (6) Disconnect the track bar from the frame rail bracket. (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 retainer bolt and remove the spring. (9) Remove the jounce bumper if necessary from the upper spring mount (Fig. 2). INSTALLATION (1) Install the jounce bumper on the upper spring mount. Tighten the bolts to 42 N·m (31 ft. lbs.). (2) Position the coil spring on the axle pad. Install the spring retainer and bolt. (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 arm to the axle. (6) Install the front propeller shaft to the axle. (7) Install drag link to pit man arm. (8) Remove the supports and lower the vehicle. (9) Tighten all suspension components to proper torque.

Fig. 3 Cam Adjuster (3) Remove the lower suspension arm nut, cam and cam bolt from the axle (Fig. 4). (4) Remove the nut and bolt from the frame rail bracket and remove the lower suspension arm (Fig. 4).

STEERING KNUCKLE For service procedures on the steering knuckle and ball studs refer to Group 3 Differentials And Driveline.

Fig. 4 Upper & Lower Suspension Arms INSTALLATION (1) Position the lower suspension arm at the axle bracket and frame rail bracket.


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SUSPENSION

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REMOVAL AND INSTALLATION (Continued) (2) Install the rear bolts and finger tighten the new nuts. (3) Install a new cam bolt, cam and new nut in the axle. Re-align the reference marks. (4) Install the bolts and finger tighten the new nuts. (5) Lower the vehicle. (6) Tighten the front and rear nuts to 115 N·m (85 ft. lbs.). (7) Check the alignment if new parts were installed.

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

Fig. 5 Bushing Removal

AXLE BUSHING REMOVAL (1) Remove the upper suspension arm from axle (2) Position Receiver 7932-1 (J-35581-1) over the bushing in the axle and install Bushing Removal/Installer (Fig. 5). (3) Remove the bushing by tightening the Long Nut. NOTE: For two-wheel drive axles and right side on Model 30 axle, do not remove Receiver 7932-1 (J-35581-1) at this time.

INSTALLATION (1) Position new bushing, Receiver and Installer on axle (Fig. 6). (2) Install the bushing by tightening the Long Nut. (3) Remove tools and install the upper suspension arm.

Fig. 6 Bushing Installation (3) Remove the stabilizer bar link nuts from the stabilizer bar. (4) Remove the stabilizer bar clamps bolts from the frame rails and remove the stabilizer bar.

STABILIZER BAR REMOVAL (1) Raise and support the vehicle. (2) Remove the stabilizer bar link nuts from the axle brackets (Fig. 7).

INSTALLATION (1) Position the stabilizer bar on the frame rail and install the clamps and bolts. Ensure the bar is centered with equal spacing on both sides. Tighten the bolts to 54 N·m (40 ft. lbs.).


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REMOVAL AND INSTALLATION (Continued)

Fig. 7 Stabilizer Bar (2) Install the links into the stabilizer bar and axle brackets. Tighten the nuts at the axle bracket finger tight. (3) Tighten the stabilizer bar to link nuts to 61 N·m (45 ft. lbs.). (4) Remove the supports and lower the vehicle. (5) Tighten the nuts at the axle bracket end to 95 N·m (70 ft. lbs.).

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. 8). NOTE: 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. 8). Remove the track bar.

INSTALLATION (1) Install the track bar at axle tube bracket. Loosely install the retaining bolt and flag nut. (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. (3) Remove the supports and lower the vehicle. (4) Tighten the bolt at the axle shaft tube bracket to 75 N·m (55 ft. lbs.). (5) Tighten the ball stud nut to 81 N·m (60 ft. lbs.). Install a new cotter pin.

Fig. 8 Track Bar (6) Check alignment if a new track bar was installed.

HUB BEARING The Hub Bearing is serviced as an assembly.

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. 9). (5) Remove the hub mounting bolts and remove hub bearing from the steering knuckle and axle shaft. INSTALLATION (1) Install the hub bearing and brake dust shield to the knuckle. (2) Install the hub to knuckle bolts and tighten to 102 N·m (75 ft. lbs.). (3) Install the hub washer and nut. Tighten the hub nut to 237 N·m (175 ft. lbs.). Install the nut retainer and a new cotter pin. (4) Install the brake components, refer to Group 5 Brakes. (5) Install the wheel and tire assembly. (6) Remove support and lower the vehicle.


SUSPENSION

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2 - 11

REMOVAL AND INSTALLATION (Continued)

Fig. 9 Hub Bearing & Knuckle

WHEEL MOUNTING STUDS REMOVAL (1) Raise and support vehicle. (2) Remove wheel and tire assembly. (3) Remove brake caliper and rotor, refer to Group 5 Brakes for procedure. (4) Remove stud from hub with Remover C-4150A (Fig. 10).

(4) Remove lug nut and washers. (5) Install the brake rotor and caliper, refer to Group 5 Brakes for procedure. (6) Install wheel and tire assembly, use new lug nut on stud or studs that were replaced. (7) Remove support and lower vehicle.

SPECIFICATIONS TORQUE CHART

Fig. 10 Wheel Stud Removal INSTALLATION (1) Install new stud into hub flange. (2) Install three washer onto stud, then install lug nut with the flat side of the nut against the washers. (3) Tighten lug nut until the stud is pulled into the hub flange. Verify that the stud is properly seated into the flange.

DESCRIPTION TORQUE Shock Absorber Upper Nut . . . . . . . . . . . . . . . . .23 N·m (17 ft. lbs.) Lower Nut. . . . . . . . . . . . . . . .28 N·m (250 in. lbs.) Suspension Arm Upper Nuts . . . . . . . . . . . . . . . . . . . . .75 N·m (55 ft. lbs.) Suspension Arm Lower Nuts. . . . . . . . . . . . . . . . . . . . .115 N·m (85 ft. lbs.) Stabilizer Bar Clamp Bolt . . . . . . . . . . . . . . . .54 N·m (40 ft. lbs.) Link Upper Nut. . . . . . . . . . . . .61 N·m (45 ft. lbs.) Link Lower Bolt . . . . . . . . . . . .95 N·m (70 ft. lbs.) Track Bar Ball Stud Nut . . . . . . . . . . . . . .81 N·m (60 ft. lbs.) Axle Bracket Bolt . . . . . . . . . . .75 N·m (55 ft. lbs.) Track Bar Bracket Bolts . . . . . . . . . . . . . . . . . . . .121 N·m (90 ft. lbs.) Nut . . . . . . . . . . . . . . . . . . . . .121 N·m (90 ft. lbs.) Support Bolts . . . . . . . . . . . . . .95 N·m (70 ft. lbs.)


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SUSPENSION

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SPECIAL TOOLS FRONT SUSPENSION

Remover/Installer Suspension Bushing 7932 (J-35581)

Bolt, Special 7604 (J-21474–19)

Nut, Long 7603 (J-21474–18)

Remover C-4150A


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REAR SUSPENSION INDEX page DESCRIPTION AND OPERATION REAR SUSPENSION . . . . . . . . DIAGNOSIS AND TESTING SHOCK DIAGNOSIS . . . . . . . . . REMOVAL AND INSTALLATION COIL SPRING . . . . . . . . . . . . . . LOWER SUSPENSION ARM . . .

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page SHOCK ABSORBER . . . . . . STABILIZER BAR . . . . . . . . TRACK BAR . . . . . . . . . . . . UPPER SUSPENSION ARM SPECIFICATIONS TORQUE CHART . . . . . . . .

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DESCRIPTION AND OPERATION REAR SUSPENSION The rear suspension is link/coil design comprised of (Fig. 1): • Drive axle • Dual-action shock absorbers • Coil springs • Upper and lower suspension arms • Track bar • Stabilizer bar • Jounce bumpers Upper And Lower Suspension: The suspension arms use bushings to isolate road noise. The suspension arms are bolted to the body and axle through the rubber bushings. The upper suspension arm has provision for the use of cam bolts at the axle to allow for pinion angle or thrust angle adjustment. The cams are available as a service kit and are not installed at the factory. The suspension arm travel is limited through the of use jounce bumpers in compression and shock absorbers in rebound. Shock Absorbers: 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 shock absorber bracket. Coil Springs: The coil springs mount up in the fender shield that is part of the unitized body bracket. There is a rubber isolator between the top of the spring and bracket to isolate road noise. The bottom of the spring seats on the axle pad and is retained with a clip. Stabilizer Bar: The stabilizer bar is used to control vehicle body roll during turns. The spring steel bar helps to equalize the vehicle body in relationship to the suspension. The bar extends across the underside of the chassis and connects to the frame rails. Links are connected from the bar to the axle brackets. Stabilizer bar are isolated by rubber bushings.

Fig. 1 Rear Suspension Track Bar: The track bar is used to control rear axle lateral movement. The track bar is attached to a frame rail bracket and an axle bracket. It is isolated with bushings at both ends. CAUTION: Suspension components that use rubber bushings should be tightened with the vehicle at normal ride height. This will prevent premature failure of the bushing and maintain ride comfort. Rubber bushings must never be lubricated.


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SUSPENSION

DIAGNOSIS AND TESTING SHOCK DIAGNOSIS A noise from a shock absorber may be caused by movement between mounting bushings and metal brackets or attaching components. This noise can usually be stopped by tightening the attaching nuts. If the noise persists, inspect for damaged and worn bushings, and attaching components. Repair as necessary if any of these conditions exist. 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 in and out of the cylinder four or five times. The action throughout each stroke should be smooth and even. The shock absorber bushings do not require any type of lubrication. Do not attempt to stop bushing noise by lubricating them. Grease and mineral oilbase lubricants will deteriorate the bushing rubber.

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INSTALLATION (1) Install the shock absorber on the upper frame rail stud. Install the shock absorber on the axle bracket. (2) Install the retainer and nut on the stud. Tighten the upper nut to 70 N路m (52 ft. lbs.). (3) Install lower bolt and nut finger tight. (4) Remove the supports and lower the vehicle. (5) Tighten the lower nut to 92 N路m (68 ft. lbs.)

COIL SPRING REMOVAL (1) Raise and support the vehicle. Position a hydraulic jack under the axle to support it. (2) Disconnect the stabilizer bar link and shock absorber from the axle bracket. (3) Disconnect the track bar from the frame rail bracket. (4) Lower the axle until the spring is free from the upper mount seat. Remove the coil spring retainer bolt (Fig. 2) and remove the spring.

REMOVAL AND INSTALLATION SHOCK ABSORBER REMOVAL (1) Raise and support the vehicle. Position a hydraulic jack under the axle to support it. (2) Remove the upper nut and retainer from the frame rail stud (Fig. 2). (3) Remove the lower nut and bolt from the axle bracket. Remove the shock absorber.

INSTALLATION Inspect isolator the for damage or wear. Replace the isolator if necessary before installing spring. (1) Position the coil spring on the axle pad. Install the spring retainer and bolt. Tighten the bolt to 22 N路m (16 ft. lbs.). (2) Raise the axle into position until the spring seats in the upper mount. (3) Connect the stabilizer bar links and shock absorbers to the axle bracket. Connect the track bar to the frame rail bracket. (4) Remove the supports and lower the vehicle. (5) Tighten the brack bar and shock absorber to specified torque.

LOWER SUSPENSION ARM REMOVAL (1) Raise and support the vehicle. (2) Remove the lower 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 lower suspension arm. INSTALLATION (1) Position the lower suspension arm at the axle bracket and frame rail bracket. (2) Install the bolts and finger tighten the nuts. (3) Remove the supports and lower the vehicle. (4) Tighten the lower suspension arm nuts to 177 N路m (130 ft. lbs.).

Fig. 2 Rear Coil Spring & Shock Absorber


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REMOVAL AND INSTALLATION (Continued) (2) Disconnect the stabilizer bar links from the axle brackets (Fig. 4). (3) Lower the exhaust by disconnecting the muffler and tail pipe hangers. (4) Disconnect the stabilizer bar from the links. (5) Disconnect the stabilizer bar clamps from the frame rails. Remove the stabilizer bar.

Fig. 3 Upper & Lower Suspension Arms

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). Remove the ABS wire bracket from the arm. (3) Remove the nut and bolt at the frame rail and remove the upper suspension arm. INSTALLATION (1) Position the upper suspension arm at the axle and frame rail. (2) Install the bolts and finger tighten the nuts. Install the ABS wire bracket onto the arm. (3) Remove the supports and lower the vehicle. (4) Tighten the upper suspension arm nuts to 75 N·m (55 ft. lbs.).

STABILIZER BAR REMOVAL (1) Raise and support the vehicle. Remove one wheel and tire.

Fig. 4 Rear Stabilizer Bar INSTALLATION (1) Position the stabilizer bar on the frame rail and install the clamps and bolts. Ensure the bar is centered with equal spacing on both sides. Tighten the bolts to 54 N·m (40 ft. lbs.). (2) Install the links and grommets onto the stabilizer bar and axle brackets. Install the nuts and tighten to 36 N·m (27 ft. lbs.). (3) Connect the muffler and tail pipe to their hangers. (4) Install the wheel and tire assembly.


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REMOVAL AND INSTALLATION (Continued)

TRACK BAR REMOVAL (1) Raise and support the vehicle. (2) Remove the bolt and nut from the frame rail bracket (Fig. 5). (3) Remove the bolt from the axle tube bracket (Fig. 5). Remove the track bar.

INSTALLATION (1) Install the track bar to the axle bracket and install a new bolt. (2) It may be necessary to pry the axle assembly over to install the track bar. Install the track bar to the frame rail bracket. Loosely install the bolt and flag nut. (3) Remove the supports and lower the vehicle. (4) Tighten the track bar bolts 100 N·m (74 ft. lbs.).

SPECIFICATIONS TORQUE CHART DESCRIPTION TORQUE Shock Absorber Upper Nut . . . . . . . . . . . . . . . . .70 N·m (52 ft. lbs.) Lower Nut . . . . . . . . . . . . . . . . .92 N·m (68 ft. lbs.) Suspension Arm Upper Nuts . . . . . . . . . . . . . . . . . . . . .75 N·m (55 ft. lbs.) Suspension Arm Lower Nuts. . . . . . . . . . . . . . . . . . . .177 N·m (130 ft. lbs.) Stabilizer Bar Clamp Bolt . . . . . . . . . . . . . . . .54 N·m (40 ft. lbs.) Link Nut . . . . . . . . . . . . . . . . . .36 N·m (27 ft. lbs.) Track Bar Frame Bracket Nut . . . . . . . . .100 N·m (74 ft. lbs.) Axle Bracket Bolt . . . . . . . . . .100 N·m (74 ft. lbs.)

Fig. 5 Rear Track Bar


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DIFFERENTIAL AND DRIVELINE CONTENTS page

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FRONT AXLE—TUBE AND MODEL 30 . . . . . . . . 15 MODEL 35 AXLE . . . . . . . . . . . . . . . . . . . . . . . . . 43

MODEL 44 AXLE . . . . . . . . . . . . . . . . . . . . . . . . . 75 PROPELLER SHAFTS . . . . . . . . . . . . . . . . . . . . . . 1

PROPELLER SHAFTS INDEX page GENERAL INFORMATION FRONT PROPELLER SHAFT . . . . . . . . . . . . . LUBRICATION . . . . . . . . . . . . . . . . . . . . . . . . PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . PROPELLER SHAFTS . . . . . . . . . . . . . . . . . . UNIVERSAL JOINTS . . . . . . . . . . . . . . . . . . . DIAGNOSIS AND TESTING RUNOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . UNBALANCE . . . . . . . . . . . . . . . . . . . . . . . . . VIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . SERVICE PROCEDURES INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . PROPELLER SHAFT ANGLE MEASUREMENT UNIVERSAL JOINT ANGLE . . . . . . . . . . . . . .

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GENERAL INFORMATION PROPELLER SHAFTS The function of a propeller shaft is to transmit power from one point to another in a smooth action. The shaft is designed to send torque through an angle from the transmission (transfer case on 4WD vehicles) to the axle (Fig. 1). The propeller shaft must operate through constantly changing relative angles between the transmission and axle. It must also be capable of changing length while transmitting torque. The axle rides suspended by springs in a floating motion. This means the propeller shaft must be able to change angles when going over various roads. This is accomplished through universal joints, which permit the propeller shaft to operate at different angles. The slip joints (or yokes) permit contraction or expansion. Tubular propeller shafts are balanced by the manufacturer with weights spot welded to the tube.

page REMOVAL AND INSTALLATION FRONT PROPELLER SHAFT . . . . . . . . . . . . . . . . 7 REAR PROPELLER SHAFT . . . . . . . . . . . . . . . . . 8 DISASSEMBLY AND ASSEMBLY DOUBLE CARDAN (CV) . . . . . . . . . . . . . . . . . . . 10 SINGLE CARDAN . . . . . . . . . . . . . . . . . . . . . . . . . 8 CLEANING AND INSPECTION SINGLE AND DOUBLE CARDAN JOINT . . . . . . . 14 ADJUSTMENTS ADJUSTMENT AT AXLE WITH LEAF SPRINGS . 14 SPECIFICATIONS TORQUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 SPECIAL TOOLS PROPELLER SHAFT . . . . . . . . . . . . . . . . . . . . . 14 The propeller shaft is designed and built with the yoke lugs in line with each other which is called phasing. This design produces the smoothest running condition. An out of phase shaft can cause a vibration. Before undercoating a vehicle, the propeller shaft and the U-joints should be covered. This will prevent the undercoating from causing an out of balance condition and vibration. CAUTION: Use exact replacement parts for attaching the propeller shafts. This will ensure safe operation. The specified torque must always be applied when tightening the fasteners.

FRONT PROPELLER SHAFT The propeller shaft has no slip yoke. This shaft uses a double cardan joint at the transfer case end and a Constant Velocity joint (CV) at the front axle end (Fig. 2). The CV joint contracts and extends


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GENERAL INFORMATION (Continued)

Fig. 1 Front & Rear Propeller Shafts—Typical 4WD which eliminates the need for a slip yoke. The CV joint has a splined shaft which allows the overall shaft length to be adjusted for optimum joint travel. This spline shaft is locked in place with a nut. Never attempt to adjust the shaft length. The overall shaft length is preset during manufacturing.

Fig. 3 Single Cardan U-Joint —Rear Fig. 2 Front Propeller Shaft

UNIVERSAL JOINTS Three different types of universal joints are used (Fig. 3), (Fig. 4) and (Fig. 5). These joints are not repairable if worn or damaged they must be replaced. If a vehicle has a damaged constant velocity joint or boot (Fig. 5), the propeller shaft must be replaced.

LUBRICATION The slip yoke on the Type 1 front shaft is equipped with a lubrication fitting. Use a multi-purpose NLGI Grade 2 EP lubricant.The factory installed U-joints are lubricated for the life of the vehicle and do not need lubrication. All U-joints should be inspected for leakage and damage each time the vehicle is serviced. If seal leakage or damage exists, the U–joint should be replaced.

PRECAUTIONS Use exact replacement hardware for attaching the propeller shafts. Exact replacement will ensure safe operation. The specified torque must always be applied when tightening the fasteners. Put reference marks on the propshaft yoke and axle or transmission yoke before service (Fig. 6). This will assure correct phasing and eliminate possible vibration. CAUTION: Do not allow the propeller shaft to drop or hang from either universal joint during removal. Attach it to the vehicle underside with wire to prevent damage to the universal joints. CAUTION: It is very important to protect the machined, external surface of the slip yoke from damage after propeller shaft removal. If damaged, the transmission extension seal could be damaged and cause a leak.


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Fig. 4 Double Cardan U-Joint —Front

Fig. 5 Constant Velocity Joint—Front

DIAGNOSIS AND TESTING VIBRATION Tires that are out–of–round or wheels that are unbalanced will cause a low frequency vibration. Refer to Group 22, Wheels and Tires for additional information. Brake drums that are unbalanced will cause a harsh, low frequency vibration. Refer to Group 5, Brakes for additional information.

Fig. 6 Reference Marks on Yokes Driveline vibration can also result from loose or damaged engine mounts. Refer to Group 21, Transmissions for additional information. Propeller shaft vibration will increase as the vehicle speed is increased. A vibration that occurs within a specific speed range is not caused by propeller shaft unbalance. Defective universal joints or an incorrect propeller shaft angle are usually the cause.


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DIAGNOSIS AND TESTING (Continued) DRIVELINE VIBRATION

UNBALANCE If propeller shaft unbalance is suspected, it can be verified with the following procedure: Removing and re–indexing the propeller shaft 180° may eliminate some vibrations. • Clean all the foreign material from the propeller shaft and the universal joints. • Inspect the propeller shaft for missing balance weights, broken welds, and bent areas. If the propeller shaft is bent, it must be replaced. • Ensure the universal joints are not worn, are properly installed, and are correctly aligned with the shaft. • Check the universal joint clamp screws torque (1) Raise the vehicle. (2) Remove the wheel and tires assembly. Install the wheel lug nuts to retain the brake drums. (3) Mark and number the shaft six inches from the yoke end at four positions 90° apart. (4) Run and accelerate the vehicle until vibration occurs. Note the intensity and speed the vibration occurred. Stop the engine. (5) Install a screw clamp at position 1 (Fig. 7). (6) Start the engine and re–check for vibration. If there is little or no change in vibration, move the clamp to one of the other three positions. Repeat the vibration test. (7) If there is no difference in vibration at the other positions, the vibration may not be propeller shaft unbalance. (8) If the vibration decreased, install a second clamp (Fig. 8) and repeat the test.

Fig. 7 Clamp Screw At Position 1

Fig. 8 Two Clamp Screws At The Same Position


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DIAGNOSIS AND TESTING (Continued) (9) If the clamps cause an additional unbalance, separate the clamps (1/4 inch above and below the mark). Repeat the vibration test (Fig. 9).

Fig. 9 Clamp Screws Separated (10) Increase distance between the clamp screws and repeat the test until the amount of vibration is at the lowest level. Bend the slack end of the clamps so the screws will not loosen. (11) Install the wheel and tires. Lower the vehicle. (12) If the amount of vibration remains unacceptable, apply procedures at the front end of the propeller shaft.

RUNOUT (1) Remove dirt, rust, paint, and undercoating from the propeller shaft surface. Areas where the dial indicator will contact the shaft must be clean. (2) The dial indicator must be installed perpendicular to the shaft surface. (3) Measure runout at the center and ends away from welds. (4) Refer to Runout Specifications chart. (5) Replace the propeller shaft if the runout exceeds the limit.

SERVICE PROCEDURES UNIVERSAL JOINT ANGLE INFORMATION When two shafts come together at any common joint, the bend that is formed is called the operating angle. The larger the angle, the larger the amount of acceleration and deceleration of the joint. This speeding up and slowing down of the joint must be cancelled to produce a smooth power flow. This is done through phasing and proper universal joint working angles. A propeller shaft is properly phased when the yoke ends are on the same plane or in line. A twisted shaft will throw the yokes out of phase and cause a noticeable vibration. When taking universal joint angle measurements or checking phasing with two piece shafts, consider each shaft separately. On 4WD vehicles, the front shaft input (pinion shaft) angle has priority over the caster angle. Ideally the driveline system should have; • Angles that are in equal or opposite within 1 degree of each other • Have a 3 degree maximum operating angle • Have at least a 1/2 degree continuous operating (propeller shaft) angle Engine speed (rpm) is the main factor though in determining maximum allowable operating angles. As a guide to maximum normal operating angles refer to the chart listed (Fig. 10).

RUNOUT SPECIFICATIONS

Fig. 10 Maximum Angles And Engine Speed

INSPECTION Before measuring universal joint angles, the following must be done. • Inflate all tires to correct pressure • Check angles in the same loaded or unloaded condition as when the vibration occurred. Propeller


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DIFFERENTIAL AND DRIVELINE

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SERVICE PROCEDURES (Continued) shaft angles will change according to the amount of load in the vehicle. Always check angles in loaded and unloaded conditions. • Check the condition of all suspension components and verify all fasteners are torqued to specifications. • Check the condition of the engine and transmission mounts and verify all fasteners are torqued to specifications.

PROPELLER SHAFT ANGLE MEASUREMENT To accurately check driveline alignment, raise and support the vehicle at the axles as level as possible. Allow the wheels and propeller shaft to turn. Remove any external bearing snap rings (if equipped) from universal joint so protractor base sits flat. (1) Rotate the shaft until transmission/transfer case output yoke bearing is facing downward. Always make measurements from front to rear. (2) Place Inclinometer on yoke bearing (A) parallel to the shaft (Fig. 11). Center bubble in sight glass and record measurement. This measurement will give you the transmission or Output Yoke Angle (A).

Fig. 12 Propeller Shaft Angle Measurement (C) (5) Rotate propeller shaft 90 degrees and place Inclinometer on pinion yoke bearing parallel to the shaft (Fig. 13). Center bubble in sight glass and record measurement. This measurement will give you the pinion shaft or Input Yoke Angle (B).

Fig. 11 Front (Output) Angle Measurement (A) (3) Rotate propeller shaft 90 degrees and place Inclinometer on yoke bearing parallel to the shaft (Fig. 12). Center bubble in sight glass and record measurement. This measurement can also be taken at the rear end of the shaft. This measurement will give you the Propeller Shaft Angle (C). (4) Subtract smaller figure from larger (C minus A) to obtain Transmission Output Operating Angle.

Fig. 13 Rear (Input) Angle Measurement (B) (6) Subtract smaller figure from larger (C minus B) to obtain axle Input Operating Angle. Refer to rules given below and the example in (Fig. 14) for additional information. • Good cancellation of U–joint operating angles (within 1°) • Operating angles less than 3°


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3-7

SERVICE PROCEDURES (Continued)

Fig. 14 Universal Joint Angle Example • At least 1/2 of one degree continuous operating (propeller shaft) angle

REMOVAL AND INSTALLATION FRONT PROPELLER SHAFT CAUTION: If front propeller shaft must be replaced, the new shaft length must be measured and adjusted before the vehicle is returned to use.

REMOVAL (1) Shift the transmission and transfer case (if applicable) to Neutral position. (2) Raise and support vehicle on safety stands. (3) Using a suitable marker, mark a line across the yoke at the transfer case and the cardan-join at the rear of the front propeller shaft. (4) Marks a line across the CV-joint and the pinion shaft yoke. NOTE: The reference marks will be used to aid installation. CAUTION: Do not loosen CV-joint lock nut or collapse the front propeller shaft. Driveline vibration can result.

(5) Remove bolts holding CV joint at front of shaft to front axle pinion yoke. (6) Remove bolts holding rear cardan-joint to the transfer case yoke. (7) Separate the cardan-joint from the transfer case yoke. (8) Push rear of propeller shaft upward to clear transfer case yoke. (9) Separate CV-joint from front axle. (10) Separate propeller shaft from vehicle.

INSTALLATION (1) Position front propeller shaft under vehicle with rear cardan-joint over the transfer case yoke. (2) Place CV-joint into axle pinion yoke. CV-joint should rotate freely in the pinion yoke. (3) Align mark on the rear cardan-joint to the mark on the transfer case yoke. (4) Loosely install bolts to hold cardan-joint to transfer case yoke. (5) Align mark on CV-joint to the mark on the axle pinion yoke. (6) Install bolts to hold CV-joint to axle pinion yoke. Tighten bolts to 41 N·m (30 ft. lbs.) (7) Tighten bolts to hold cardan-joint to transfer case yoke to 27 N·m (20 ft. lbs.) (8) Lower vehicle and road test to verify repair.


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REMOVAL AND INSTALLATION (Continued) MEASUREMENT This measurement is taken with the shaft installed and the vehicle at proper ride height. (1) Place vehicle on floor or drive-on hoist with full weight of vehicle on suspension. (2) Take a measure from the CV-joint cup to the end of the CV-joint boot (Fig. 15).

(2) Scribe alignment marks at the pinion shaft and at each end of the propeller shaft. These marks will be used for installation reference. (3) Remove the U–joint strap bolts at the pinion shaft yoke. (4) Slide the slip yoke off of the transmission/ transfer case output shaft and remove the propeller shaft (Fig. 17).

Fig. 15 Measurement (3) Adjust by loosening the lock nut and moving the one end of the shaft in or out of the other end. (4) When the shaft is adjusted to the correct length (Fig. 15) 142.7 mm (5.61 in.) tighten the locknut (Fig. 16) to 115 N·m (85 ft. lbs.).

Fig. 17 Rear Propeller Shaft

Fig. 16 Lock–nut CAUTION: A propeller shaft that has been in use for a long period of time cannot be adjusted. If the length of the propeller is incorrect and causing vibration, replace the propeller shaft.

REAR PROPELLER SHAFT REMOVAL (1) Shift the transmission and transfer case (if applicable) to their Neutral positions. Raise the vehicle.

INSTALLATION (1) Slide the slip yoke on the transmission/transfer case output shaft. Align the installation reference marks at the axle yoke and install the propeller shaft (Fig. 17). Replacement U–joint straps and bolts must be installed. (2) Tighten the U–joint strap/clamp bolts at the axle yoke to 19 N·m (14 ft. lbs.) torque. (3) Lower the vehicle.

DISASSEMBLY AND ASSEMBLY SINGLE CARDAN REMOVAL Single cardan universal joints are not serviceable. If worn or leaking, they must be replaced as a unit. (1) Remove the propeller shaft. Refer to Propeller Shaft Replacement in this Group. (2) Paint or score alignment marks on the yokes and propeller shaft for installation reference.


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DISASSEMBLY AND ASSEMBLY (Continued) (3) Using a soft drift, tap the outside of the bearing assembly to loosen snap ring. (4) Remove snap rings from both sides of yoke (Fig. 18).

(6) If the bearing assembly will not pull out by hand after pressing, tap the base of the lug near it to dislodge. (7) To remove the opposite bearing, turn the yoke over and straighten the cross in the open hole. Then carefully press the end of the cross until the remaining bearing can be removed (Fig. 20). CAUTION: If the cross or bearing assembly are cocked when being pressed, the bearing assembly will score the walls of the yoke bore and ruin the yoke.

Fig. 18 Remove Snap Ring (5) Set the yoke in an arbor press or vise with a large socket beneath it. Position the yoke with the grease fitting pointing up (if equipped). Place a smaller socket on the upper bearing assembly and press it through to release the lower bearing assembly (Fig. 19).

Fig. 20 Press Out Remaining Bearing

Fig. 19 Press Out Bearing


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DIFFERENTIAL AND DRIVELINE

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DISASSEMBLY AND ASSEMBLY (Continued) ASSEMBLY (1) Apply extreme pressure (EP) N.L.G.I. Grade 1 or 2 grease to aid in installation. (2) Position the cross in the yoke with its lube fitting (if equipped) pointing up (Fig. 21).

(4) Press the bearing assembly into the cross hole enough to install a snap ring. Install a snap ring. (5) Repeat steps 3 and 4 to install the opposite bearing assembly. If the joint is stiff, strike the yoke with a soft hammer to seat the needle bearings. Install a snap ring. (6) Add grease to lube fitting (if equipped). (7) Install the propeller shaft.

DOUBLE CARDAN (CV) REMOVAL Cardan universal joints are not serviceable. If worn or leaking, they must be replaced as a unit. (1) Remove the propeller shaft. Refer to Propeller Shaft Replacement in this Group. (2) Paint or score alignment marks on the yokes and propeller shaft for installation reference. (3) Remove all the bearing assembly snap rings (Fig. 23).

Fig. 21 Install Cross In Yoke (3) Place a bearing assembly over the trunnion and align it with the cross hole (Fig. 22). Keep the needle bearings upright in the bearing assembly. A needle roller lying at the bottom will prevent proper assembly.

Fig. 23 Remove Snap Rings

Fig. 22 Install Bearing On Trunnion


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DISASSEMBLY AND ASSEMBLY (Continued) (4) Press the bearing assembly partially from the outboard side of the center yoke, enough to grasp by vise jaws (Fig. 24). Be sure to remove grease fittings that interfere with removal.

Fig. 24 Press Out Bearing (5) Grasp the protruding bearing by vise jaws. Tap the tube yoke with a mallet and drift to dislodge from the yoke (Fig. 25).

(6) Flip assembly and repeat steps 4 and 5 for removing the opposite side bearing. This will then allow removal of the cross centering kit assembly and spring (Fig. 26).

Fig. 26 Remove Centering Kit (7) Press the remaining bearing assemblies out the other cross as described above to complete the disassembly.

INSTALLATION During installation, ensure that the spiders and yokes are aligned to the reference marks. (1) Fit a cross into the tube yoke (Fig. 27).

Fig. 25 Remove Bearing From Yoke

Fig. 27 Install Cross In Yoke


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DISASSEMBLY AND ASSEMBLY (Continued) (2) Place a bearing assembly in a tube yoke hole and over a trunnion. Keep the needle bearings upright in the bearing assembly (Fig. 28). A needle roller lying at the bottom will prevent proper assembly. Be sure to remove any lube fittings that may interfere with removal.

(4) Flip the tube yoke and bearing assembly installation on the opposite trunnion. Install a snap ring (Fig. 30).

Fig. 30 Press In Bearing Assembly Fig. 28 Install Bearing Assembly (3) Press the bearing assembly in place and install a snap ring (Fig. 29).

(5) Fit the center yoke on the remaining two trunnions and press bearing assemblies in place, both sides (Fig. 31). Install a snap ring.

Fig. 31 Install Center Yoke Fig. 29 Press In Bearing Assembly


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DISASSEMBLY AND ASSEMBLY (Continued) (6) Install the centering kit assembly inside the center yoke making sure the spring is in place (Fig. 32).

Fig. 32 Install Centering Kit (7) Place two bearing assemblies on the remaining cross (opposite sides). Fit the open trunnions into the center yoke holes and the bearing assemblies into the centering kit (Fig. 33).

Fig. 33 Install Remaining Cross

(8) Press the remaining two bearing assemblies into place and install snap rings (Fig. 34).

Fig. 34 Press In Bearing Assembly (9) Tap the snap rings to allow them to seat into the grooves (Fig. 35).

Fig. 35 Seat Snap Rings In Groove (10) Check for proper assembly. Flex the CV joint beyond center, it should snap over–center in both directions when correctly assembled (Fig. 36). (11) Install the propeller shaft.


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Adjust the pinion gear angle at the lower suspension arms with shims (Fig. 38). Adding shims will decrease the pinion gear shaft angle but will increase the caster angle. The pinion gear shaft angle has priority over the caster angle.

Fig. 36 Check Assembly

CLEANING AND INSPECTION SINGLE AND DOUBLE CARDAN JOINT (1) Clean all the universal joint yoke bores with cleaning solvent and a wire brush. (2) Inspect the yokes for distortion, cracks and worn bearing assembly bores.

Fig. 38 Front Axle Angle Adjustment

SPECIFICATIONS TORQUE

ADJUSTMENTS ADJUSTMENT AT AXLE WITH LEAF SPRINGS Adjust the pinion shaft angle at the springs with tapered shims (Fig. 37). Install tapered shims between the springs and axle pad to correct the angle.

DESCRIPTION Front Propeller Shaft Bolts, Rear Yoke . . . . . . . . . . . . . .27 Bolts, Front Yoke . . . . . . . . . . . . .41 Nut, Lock . . . . . . . . . . . . . . . . . .115 Rear Propeller Shaft Bolts, Rear Yoke . . . . . . . . . . . . . .19

SPECIAL TOOLS PROPELLER SHAFT

Fig. 37 Angle Adjustment at Leaf Springs

Inclinometer—7663

TORQUE N·m (20 ft. lbs.) N·m (30 ft. lbs.) N·m (85 ft. lbs.) N·m (14 ft. lbs.)


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FRONT AXLE—TUBE AND MODEL 30 INDEX page GENERAL INFORMATION INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . LUBRICATION SPECIFICATIONS . . . . . . . . . . . . PINION GEAR DEPTH INFORMATION . . . . . . . . DIAGNOSIS AND TESTING DRIVELINE SNAP . . . . . . . . . . . . . . . . . . . . . . . FRONT DRIVE AXLE . . . . . . . . . . . . . . . . . . . . . GEAR AND BEARING NOISE . . . . . . . . . . . . . . . GENERAL INFORMATION . . . . . . . . . . . . . . . . . LOW SPEED KNOCK . . . . . . . . . . . . . . . . . . . . . VIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . SERVICE PROCEDURES LUBRICANT CHANGE . . . . . . . . . . . . . . . . . . . . REMOVAL AND INSTALLATION AXLE BUSHING REPLACEMENT . . . . . . . . . . . . DIFFERENTIAL . . . . . . . . . . . . . . . . . . . . . . . . . DRIVE AXLE ASSEMBLY REPLACEMENT . . . . . HUB BEARING AND AXLE SHAFT . . . . . . . . . . . INNER AXLE SHAFT OIL SEAL REPLACEMENT . PINION GEAR . . . . . . . . . . . . . . . . . . . . . . . . . .

15 15 16 18 19 17 17 18 18 21 25 25 21 23 27 27

GENERAL INFORMATION INFORMATION The Model 30 front axle 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. Do not damage ABS tone wheel or the sensor when removing axle shafts. 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

page PINION SEAL REPLACEMENT . . . . . . . . . . . . STEERING KNUCKLE AND BALL STUDS . . . . DISASSEMBLY AND ASSEMBLY AXLE SHAFT—CARDAN U-JOINT . . . . . . . . . BACKLASH AND CONTACT PATTERN ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . DIFFERENTIAL AND PINION MEASUREMENT DIFFERENTIAL SHIM PACK MEASUREMENT AND ADJUSTMENT . . . . . . . . . . . . . . . . . . . DIFFERENTIAL . . . . . . . . . . . . . . . . . . . . . . . FINAL ASSEMBLY . . . . . . . . . . . . . . . . . . . . . CLEANING AND INSPECTION CARDAN U-JOINT . . . . . . . . . . . . . . . . . . . . . DIFFERENTIAL . . . . . . . . . . . . . . . . . . . . . . . SPECIFICATIONS FRONT AXLE—MODEL 30 . . . . . . . . . . . . . . TORQUE—MODEL 30 AXLE . . . . . . . . . . . . . . SPECIAL TOOLS FRONT AXLE—MODEL 30 . . . . . . . . . . . . . . .

. . 22 . . 24 . . 30 . . 36 . . 33 . . 35 . . 31 . . 38 . . 38 . . 38 . . 38 . . 38 . . 39

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.

SELEC–TRAC The Selec–Trac system is a non–disconnect axle. Shifting from two– wheel to four–wheel drive is done at the transfer case. Vehicles equipped with Selec–Trac and ABS brake system, refer to Group 5—Brakes for additional service information.

LUBRICATION 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. Mopar 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.


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GENERAL INFORMATION (Continued) • 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. CAUTION: If axle is submerged in water, lubricant must be replaced immediately to avoid possible premature axle failure.

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. 1). 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. 2). The standard depth provides the best teeth contact pattern.

Fig. 1 Pinion Gear ID Numbers 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. 2). 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. 3). 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

Fig. 2 Pinion Gear Head and the thickness included with the total shim pack.

Fig. 3 Shim Locations 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 in. (0.10 mm). Add this amount to the original shim. Or if the old pinion is (–) 3 and the new pinion is (–)


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GENERAL INFORMATION (Continued) PINION GEAR DEPTH VARIANCE

2, intersecting figure is (–) 0.001 in. (0.025 mm). Subtract this amount from original shim. Refer to the Pinion Gear Depth Variance Chart.

DIAGNOSIS AND TESTING GENERAL INFORMATION 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 spin 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 AND BEARING NOISE 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


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DIAGNOSIS AND TESTING (Continued) 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. 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: • 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, 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 DRIVE AXLE

DIAGNOSIS

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DIAGNOSIS AND TESTING (Continued) CONTINUED


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SERVICE PROCEDURES

REMOVAL AND INSTALLATION

LUBRICANT CHANGE

DRIVE AXLE ASSEMBLY REPLACEMENT

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 Mopar Silicone Rubber Sealant to the housing cover (Fig. 4). Allow the sealant to cure for a few minutes.

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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. 4 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 N·m (30 ft. lbs.) torque. (8) Refill the differential with Mopar 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 N·m (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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REMOVAL AND INSTALLATION (Continued) (6) Install the shock absorber and tighten the bolt to 23 N·m (17 ft. lbs.) torque. (7) Install the stabilizer bar link to the axle bracket. Tighten the nut to 95 N·m (70 ft. lbs.) torque. (8) Install the drag link and tie rod to the steering knuckles and tighten the nuts to 47 N·m (35 ft. lbs.) torque. Install the steering damper to the axle bracket and tighten the nut to 75 N·m (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 N·m (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 N·m (55 ft. lbs.) torque. Tighten the lower suspension arm nuts to 115 N·m (85 ft. lbs.) torque. (16) Tighten the track bar bolt at the axle bracket to 100 N·m (74 ft. lbs.) torque. (17) Check the front wheel alignment.

(7) Use Remover 7794A and slide hammer to remove the pinion gear seal (Fig. 6).

Fig. 6 Seal Removal 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. 7).

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. 5). (6) Mark the positions of the yoke and pinion gear for installation alignment reference.

Fig. 7 Pinion Seal Installation

Fig. 5 Pinion Yoke Removal

(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 using hloding tool 6958 and a torque wrench (Fig. 8). Tighten the nut to 217–352 N·m (160–260 ft. lbs.). Refer to Pinion Gear removal and installation section of this group. (4) Align the installation reference marks and attach the propeller shaft to the yoke.


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REMOVAL AND INSTALLATION (Continued) (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. 9). (5) Remove the hub to knuckle bolts (Fig. 9). Remove the hub from the steering knuckle and axle shaft. (6) Remove the disc brake rotor shield from the bearing carrier (Fig. 9). (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.

Fig. 8 Tighten Pinion Nut (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 REMOVAL (1) Raise and support the vehicle. (2) Remove the wheel and tire assembly.

INSTALLATION (1) Thoroughly clean the axle shaft (Fig. 9) 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 N·m (75 ft. lbs.) torque. (5) Install the hub washer and nut. Tighten the hub nut to 237 N·m (175 ft. lbs.) torque. Install the nut retainer and a new cotter pin (Fig. 9). (6) Install the brake components, refer to Group 5, Brakes. (7) Install the wheel and tire assembly.

Fig. 9 Hub, Knuckle and Axle Shaft


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REMOVAL AND INSTALLATION (Continued) (8) Remove support and lower the vehicle.

STEERING KNUCKLE AND BALL STUDS 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). 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. 10).

Fig. 10 Steering Knuckle Removal/Installation

UPPER BALL STUD REPLACEMENT (1) Position tools as shown to remove and install ball stud (Fig. 11).

Fig. 11 Upper Ball Stud Remove/Install


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REMOVAL AND INSTALLATION (Continued)

Fig. 12 Lower Ball Stud Remove/Install LOWER BALL STUD REPLACEMENT (1) Position tools as shown to remove and install ball stud (Fig. 12). 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. (2) Install and tighten the bottom retaining nut to 109 N·m (80 ft. lbs.) torque. Install new cotter pin. (3) Install and tighten the top retaining nut to 101 N·m (75 ft. lbs.) torque. Install new cotter pin. (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.

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. 13).

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

Fig. 13 Bearing Cap Identification


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REMOVAL AND INSTALLATION (Continued) (2) Remove the differential bearing caps. (3) Position Spreader W–129–B with the tool dowel pins seated in the locating holes (Fig. 14). Install the holddown clamps and tighten the tool turnbuckle finger–tight.

Fig. 14 Spread Differential Housing (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. 14) and zero the indicator.

Fig. 15 Differential Removal

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. 14). (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. 15). (8) Remove the case from housing. Mark or tag bearing cups indicating which side they were removed. Remove spreader from housing.

INSTALLATION (1) Position Spreader W–129–B with the tool dowel pins seated in the locating holes (Fig. 16). Install the holddown clamps and tighten the tool turnbuckle finger–tight. (2) Install a pilot stud at the left side of the differential housing. Attach Dial Indicator to housing pilot

Fig. 16 Spread Differential Housing stud. Load the indicator plunger against the opposite side of the housing (Fig. 16) 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. (3) Spread the housing enough to install the case in the housing. Measure the distance with the dial indicator (Fig. 16). (4) Remove the dial indicator.


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REMOVAL AND INSTALLATION (Continued) (5) Install case in the housing. Tap the differential case to ensure the bearings are fully seated (Fig. 17). Remove the spreader.

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–112A (Fig. 19). Tighten tool until disc bottoms in housing.

Fig. 17 Differential Installation (6) Install the bearing caps at their original locations (Fig. 18). Tighten the bearing cap bolts to 61 N·m (45 ft. lbs.) torque.

Fig. 19 Axle Seal Installation

PINION GEAR REMOVAL/DISASSEMBLY (1) Remove the pinion yoke nut and washer. Use Remover C–452 and Wrench C–3281 to remove the pinion yoke (Fig. 20).

Fig. 18 Differential Bearing Cap Reference Letters

Fig. 20 Pinion Yoke Removal


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REMOVAL AND INSTALLATION (Continued) (2) Remove the pinion gear seal with a slide hammer or pry out with bar. (3) Drive out pinion gear from housing with rawhide or plastic hammer (Fig. 21). 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.

(6) Remove the rear bearing cup from housing (Fig. 23). Use Remover D– 149 and Handle C–4171.

Fig. 23 Rear Bearing Cup Removal (7) Remove the inner bearing from the pinion with Puller C–293PA and Adapter C–293–39 (Fig. 24). Place adapter rings so they do not damage the bearing cage.

Fig. 21 Remove Pinion Gear (4) Remove front bearing from housing. (5) Remove the front pinion bearing cup and seal with Remover D–147 and Handle C–4171 (Fig. 22).

Fig. 24 Inner Bearing Removal (8) Remove the oil slinger from the pinion gear shaft. Save the slinger it is used as select shim for pinion depth.

Fig. 22 Front Bearing Cup Removal


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Fig. 26 Pinion Seal Installation

Fig. 25 Pinion Rear Bearing Installation (3) Assemble preload shims onto pinion shaft. (4) Install pinion front bearing cone into cup and end yoke thrust washer. (5) Apply a light coat of gear lubricant on lip of new pinion seal. Install seal with Installer D–163 and Handle C–4171 (Fig. 26). (6) Install pinion gear into differential housing. (7) Install yoke with Installer W–162D and Holder 6958 (Fig. 27).

Fig. 27 Pinion Yoke Installation

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REMOVAL AND INSTALLATION (Continued) (8) Install the yoke washer and old nut on the pinion gear. Use Holder 6958 to retain the yoke (Fig. 28). Tighten nut to 216– 352 N·m (160–260 ft. lbs.) torque.

• Original Bearings: 1 to 3 N·m (10 to 20 in. lbs.). • New Bearings: 2 to 5 N·m (15 to 35 in. lbs.). (10) If rotating torque is high, add shims to decrease torque. If rotating torque is low, remove shims to increase torque.

DISASSEMBLY AND ASSEMBLY 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. 30).

Fig. 28 Tightening Pinion Nut (9) Check bearing rotating torque with an inch pound torque wrench (Fig. 29). If torque to rotate is within specification, remove old nut and install new nut. The torque necessary to rotate the pinion gear should be;

Fig. 30 Axle Shaft Outer U–Joint It can be helpful to saturate the bearing caps with penetrating oil prior to removal. (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. 31). (3) Compress the vise jaws to force the bearing cap into the larger socket (receiver).

Fig. 29 Check Pinion Gear Torque


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DISASSEMBLY AND ASSEMBLY (Continued)

Fig. 31 Yoke Bearing Cap Removal (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. (6) Remove the remaining bearing cap, bearings, seals and spider from the propeller shaft yoke.

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. 32 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. 33).

DIFFERENTIAL DISASSEMBLY (1) Remove the bearings from the differential case with Press C–293PA, Plug C–293–3, Adapter C–293–39 (Fig. 32). Place adapter rings so they do not damage the bearing cage.

Fig. 33 Ring Gear Removal


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DISASSEMBLY AND ASSEMBLY (Continued) (4) Use a drift to remove the pinion gear mate shaft lock pin (Fig. 34).

Fig. 36 Pinion Mate Gear Removal Fig. 34 Mate Shaft Lock Pin Removal (5) Remove the mate shaft with a drift and hammer (Fig. 35).

• 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. 35 Mate Shaft Removal (6) Rotate the differential side gears and remove the pinion mate gears and thrust washers (Fig. 36). (7) Remove the differential side gears and thrust washers. (8) Remove the case from the vise.

DIFFERENTIAL ASSEMBLY (1) Install the following components in the differential case (Fig. 37). • Differential side gears and thrust washers • Pinion gears and thrust washers

Fig. 37 Mate Shaft Pin Installation


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DISASSEMBLY AND ASSEMBLY (Continued) (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 N·m (70–90 ft. lbs.) torque (Fig. 38).

Fig. 39 Master Bearing Tools On Hubs

Fig. 38 Ring Gear Bolt Installation (5) Lubricate all differential hypoid gear lubricant.

components

with

DIFFERENTIAL AND PINION MEASUREMENT DIFFERENTIAL ZERO END PLAY MEASUREMENT (1) Place Master Differential Bearing D–134 (D–348) on the case hubs (Fig. 39). 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. 40). (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. 40). Zero the dial indicator pointer. (4) Pry the case to left side and record the travel distance. 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.

Fig. 40 Differential Case End Play Measurement PINION GEAR DEPTH MEASUREMENT Pinion gear depth measurement is necessary when; • 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. 41).


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DISASSEMBLY AND ASSEMBLY (Continued)

Fig. 43 Pinion Rear Bearing Cup Installation Fig. 41 Pinion Gear Depth Gauge Tools (1) Install the pinion front bearing cup with Installer D–144 and Handle C–4171 (Fig. 42).

Fig. 44 Pinion Height Block

Fig. 42 Pinion Front Bearing Cup Installation (2) Install the bearing cup with Installer D–146 and Driver Handle C– 4171 (Fig. 43). Ensure cup is correctly seated. (3) Assemble Pinion Gauge Set, Pinion Block and pinion bearings. Install assembly into differential pinion gear bore and hand tighten cone (Fig. 44). (4) Place Arbor Disc 6732 on Arbor D–115–3 and position in the bearing cradles (Fig. 45). 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.

Fig. 45 Gauge Tools In Housing


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DISASSEMBLY AND ASSEMBLY (Continued) (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 observing indicator (Fig. 46). Record the longest travel distance, whether inward (–) or outward (+), indicated by the pointer.

Fig. 47 Shim Pack Measurement Fig. 46 Pinion Depth Measurement 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.

placed at the ring gear side between the case and bearing.

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. 47). Ensure ring and pinion gear teeth are tightly meshed. Zero the indicator. (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. 47). 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. 48). The shims must be

Fig. 48 Shim Pack Calculations (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 bear-


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DISASSEMBLY AND ASSEMBLY (Continued) ing on the hub with Bearing Installer C– 3716A and Driver Handle C–4171 (Fig. 49).

Fig. 50 Ring Gear Backlash Measurement

Fig. 49 Differential Bearing Installation (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–3716A and Handle C–4171 (Fig. 49). (11) Match each bearing cup with bearing (original). Install the cups on the bearings.

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. 50). 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. 51). 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 speci-

Fig. 51 Backlash Shim Adjustment fied 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. (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. (4) Note patterns in compound. Refer to (Fig. 52) for interpretation of contact patterns and adjust accordingly.


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Fig. 52 Gear Tooth Contact Patterns

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DISASSEMBLY AND ASSEMBLY (Continued)

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 Mopar Silicone Rubber Sealant on the housing cover. 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 N·m (30 ft. lbs.) torque. CAUTION: Overfilling the differential can result in lubricant foaming and overheating. (4) Refill the differential housing with the specified quantity of Mopar Hypoid Gear Lubricant. (5) Install the fill hole plug and tighten to 34 N·m (25 ft. lbs.) torque.

CLEANING AND INSPECTION CARDAN U-JOINT (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.

DIFFERENTIAL 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 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. • 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.

SPECIFICATIONS FRONT AXLE—MODEL 30 Axle Type . . . . . . . . . . . . . . . . . . . . . . . . . . . .Hypoid Lubricant. . . . . . . . . .SAE Thermally Stable 80W–90 Lube Capacity . . . . . . . . . . . . . . . . .1.48 L (3.13 pts.) Axle Ratio . . . . . . . . . . . . . . . . . . .3.07 3.55 3.73 4.10 Differential. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Side Gear Clearance .0.12–0.20 mm (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 N·m (10–20 in. lbs.) New Bearing . . . . . . . . . . .1.5–4 N·m (15–35 in. lbs.)

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


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SPECIAL TOOLS FRONT AXLE—MODEL 30

Adapter—C-293-48

Puller—C-293-PA

Puller—C-452

Extension—C293–3

Wrench—C-3281

Adapter—C-293-39

Dial Indicator—C-3339

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SPECIAL TOOLS (Continued)

Driver—C-3716-A

Installer—D-146

Remover—D-147

Handle—C-4171

Remover—D-148

Installer—D-112

Remover—D-149

Installer—D-144


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Installer—D163

Remover/Installer—6289

Installer—W-162-D

Tool Set, Pinion Depth—6774

Installer—6228 Installer—6764

Remover/Installer—6288 Puller—7794-A

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SPECIAL TOOLS (Continued)

Remover—7916

Support—7919

Installer—7917

Remover—7920

Screw, Forcing—7918


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MODEL 35 AXLE INDEX page GENERAL INFORMATION GENERAL INFORMATION . . . . . . . LUBRICANT SPECIFICATIONS . . . . DESCRIPTION AND OPERATION AXLES . . . . . . . . . . . . . . . . . . . . . . TRAC-LOK OPERATION . . . . . . . . . DIAGNOSIS AND TESTING DRIVELINE SNAP . . . . . . . . . . . . . GEAR AND BEARING NOISE . . . . . GENERAL INFORMATION . . . . . . . LIMITED SLIP DIFFERENTIAL . . . . LOW SPEED KNOCK . . . . . . . . . . . REAR AXLE ALIGNMENT . . . . . . . . SERVICE DIAGNOSIS . . . . . . . . . . TRAC-LOK NOISE DIAGNOSIS . . . VIBRATION . . . . . . . . . . . . . . . . . . SERVICE PROCEDURES LUBRICANT CHANGE . . . . . . . . . . REMOVAL AND INSTALLATION AXLE SHAFT SEAL AND BEARING AXLE SHAFT . . . . . . . . . . . . . . . . . DIFFERENTIAL SIDE BEARINGS . .

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47 46 46 47 46 47 48 50 46

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GENERAL INFORMATION 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 center line of the pinion set below the center line 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.

page DIFFERENTIAL . . . . . . . . . . . . . . . . . . . . . . . . DRIVE AXLE ASSEMBLY REPLACEMENT—XJ VEHICLES . . . . . . . . . . . . . . . . . . . . . . . . . . . FINAL ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . PINION GEAR . . . . . . . . . . . . . . . . . . . . . . . . . PINION SHAFT SEAL REPLACEMENT . . . . . . . RING GEAR . . . . . . . . . . . . . . . . . . . . . . . . . . . DISASSEMBLY AND ASSEMBLY STANDARD DIFFERENTIAL . . . . . . . . . . . . . . TRAC-LOK DIFFERENTIAL . . . . . . . . . . . . . . . CLEANING AND INSPECTION AXLE COMPONENTS . . . . . . . . . . . . . . . . . . . . TRAC-LOK . . . . . . . . . . . . . . . . . . . . . . . . . . . . ADJUSTMENTS DIFFERENTIAL BEARING PRELOAD AND GEAR LASH . . . . . . . . . . . . . . . . . . . . . . . . . PINION GEAR DEPTH . . . . . . . . . . . . . . . . . . . SPECIFICATIONS MODEL 35 AXLE . . . . . . . . . . . . . . . . . . . . . . . MODEL 35 AXLE . . . . . . . . . . . . . . . . . . . . . . . SPECIAL TOOLS FRONT AXLE—MODEL 35 . . . . . . . . . . . . . . . .

. 54 . . . . .

51 60 57 51 55

. 61 . 61 . 65 . 65

. 67 . 65 . 71 . 71 . 71

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. The lubricant should have MIL–L–2105C and API GL 5 quality specifications. Mopar Hypoid Gear Lubricant conforms to both of these specifications. • Lubricant is a thermally stable SAE 80W–90 gear lubricant. • Lubricant for axle with Trailer Tow is SAE 75W–140 SYNTHETIC gear lubricant. • Trac–Lok differentials add 4 oz. of friction modifier. • Lubricant capacity is 1.66 L (3.50 pts.).


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GENERAL INFORMATION (Continued) CAUTION: If axle is submerged in water, lubricant must be replaced immediately to avoid possible premature axle failure.

DESCRIPTION AND OPERATION AXLES The Model 35 axle is standard for XJ 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.

Fig. 1 Model 35 Differential Cover

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 3.0–inch (76.2 mm) in diameter. 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 • 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

Fig. 2 Differential Cover–8 1/4 • 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).


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DESCRIPTION AND OPERATION (Continued) clutch packs contain multiple disc. The clutch will have radial grooves on the plates, and concentric grooves on the discs or bonded fiber material that is smooth appearance. In operation, the Trac-lok clutches are engaged by two concurrent forces. The first being preload force exerted through Belleville spring washers contained in the clutch packs. The second from separating forces generated by the side gears as torque is applied through the ring gear (Fig. 5).

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. 5 Trac-lok Limited Slip Differential Operation

Fig. 4 Differential Operation—On Turns

TRAC-LOK OPERATION In a conventional differential, the torque applied to the ring gear is transmitted to the axle shafts through the differential gears. During normal operation, the torque transmitted to each wheel is equal at all times. However, if one wheel spins, the opposite wheel will generate only as much torque as the spinning wheel. In the Trac-lok differential, part of the ring gear torque is transmitted through clutch packs. The

The Trac-lok design provides differential action needed for turning corners and for driving straight ahead. However, when one wheel looses traction, the clutch packs transfer additional torque to the wheel having the most traction. Trac-lok differentials resist wheel spin on bumpy roads and provide more pulling power when one wheel looses traction. Pulling power is provided continuously until both wheels loose traction. If both wheels slip due to unequal traction, Trac-lok operation is normal. In extreme cases of differences of traction, the wheel with the least traction may spin.


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DIAGNOSIS AND TESTING GENERAL INFORMATION 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. 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 galling 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. Misadjustment will produce enough noise to cause service repair before a failure occurs. If a misadjustment 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 AND BEARING NOISE 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

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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. The side 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. 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


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DIAGNOSIS AND TESTING (Continued) • 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/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.

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. (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 dis-

tance 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 in. (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–Loky 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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SERVICE DIAGNOSIS

SERVICE DIAGNOSIS

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SERVICE DIAGNOSIS (CONT’D)

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TRAC-LOK NOISE DIAGNOSIS If a noise occurs when turning corners, the most probable cause is incorrect or contaminated lubricant. Before removing the Trac-lok unit for repair, drain, flush and refill the axle with the specified lubricant. Refer to Lubricant change in this Group. A container of Trac-lok Lubricant (friction modifier) should be added after repair service or a lubricant change. Vehicles with a limited slip differential 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 or pop noise complaint. Refer to Group 0, Lubrication and Maintenance for additional information.

DIFFERENTIAL TEST WARNING: WHEN SERVICING VEHICLES WITH A LIMITED SLIP DIFFERENTIAL DO NOT USE THE ENGINE TO TURN THE AXLE AND WHEELS. BOTH REAR WHEELS MUST BE RAISED AND THE VEHICLE SUPPORTED. A LIMITED SLIP AXLE CAN EXERT ENOUGH FORCE (IF ONE WHEEL IS IN CONTACT WITH THE SURFACE) TO CAUSE THE VEHICLE TO MOVE.

(6) If rotating torque is less than 22 N·m (30 ft. lbs.) or more than 271 N·m (200 ft. lbs.) on either wheel the unit should be service.

SERVICE PROCEDURES 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 Mopar Silicone Rubber Sealant to the housing cover (Fig. 7). Allow the sealant to cure for a few minutes.

The differential can be tested without removing the differential case by measuring rotating torque. Make sure brakes are not dragging during this measurement. (1) Engine off, transmission in neutral, and parking brake off. (2) Place blocks in front and rear of both front wheels. (3) Raise one rear wheel until it is completely off the ground. (4) Remove wheel and bolt Special Tool 6790 to studs. (5) Use torque wrench on special tool to rotate wheel and read rotating torque (Fig. 6).

Fig. 7 Typical Housing Cover With Sealant Install the housing cover within 5 minutes after applying the sealant. (7) Install the cover and any identification tag. Tighten the cover bolts to 41 N·m (30 ft. lbs.) torque. (8) Refill differential with Mopar Hypoid Gear Lubricant to bottom of the fill plug hole. CAUTION: Overfilling the differential can result in lubricant foaming and overheating.

Fig. 6 Trac-loc Test


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SERVICE PROCEDURES (Continued) 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.

REMOVAL AND INSTALLATION DRIVE AXLE ASSEMBLY REPLACEMENT 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. (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

(5) Connect the brake hose at the axle junction block. (6) Install the shock absorbers to the axle brackets and tighten to 62 N·m (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 N·m (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.

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 Newton–meters 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. 8). (8) Mark the positions of the yoke and pinion gear for installation alignment reference.

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 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 N·m (52 ft. lbs.) torque. (4) Install ABS wiring connections (if equipped) at the axle.

Fig. 8 Pinion Yoke Removal


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REMOVAL AND INSTALLATION (Continued) (9) Use Remover 7794A and slide hammer to remove the pinion gear seal (Fig. 9).

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 N·m (5 in. lbs.). (6) Use Flange Wrench C–3281 to retain the yoke and shaft (Fig. 11). Tighten the shaft nut in very small increments.

Fig. 9 Seal Removal 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. 10).

Fig. 11 Tightening Pinion Shaft Nut

Fig. 10 Pinion Seal Installation (2) Align the installation reference marks and install yoke on the pinion gear with Installer W–162D. (3) Install a new nut on the pinion gear. Tighten the nut only enough to remove the shaft end play.

(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. (11) Lower the vehicle.


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AXLE SHAFT 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. 12).

(9) Inspect axle shaft seal for leakage or damage. (10) Inspect the roller bearing contact surface on the axle shaft for signs of brinelling, galling 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 N·m (14 ft. lbs.) torque. (4) Install the cover and add fluid. Refer to the Drain and Refill in this section.

AXLE SHAFT SEAL AND BEARING

Fig. 12 Mate Shaft Lock Screw (7) Force the axle shaft in toward the center of the vehicle. Remove the axle shaft C–clip lock from the axle shaft (Fig. 13).

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. 14) with Bearing Removal Tool Set 6310. (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.

Fig. 13 Axle Shaft C–Clip Lock (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.

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. 15) with Installer 6437 and Handle C–4171. (4) Install the Axle Shaft. Refer to the installation procedure.


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Fig. 16 Bearing Cap Identification

Fig. 14 Axle Shaft Bearing Removal Tool

Fig. 17 Spread Differential Housing

Fig. 15 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. 16). (2) Remove the differential bearing caps. (3) Position Spreader W–129–B with the tool dowel pins seated in the locating holes (Fig. 17). Install the hold down 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. 17) 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. (5) Separate the housing enough to remove the case from the housing. Measure the distance with the dial indicator (Fig. 17). (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. 18). (8) Remove the case from housing. Mark or tag bearing cups and outboard shim/spacer (selected thickness) indicating which side they were removed.


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Fig. 18 Differential Removal

Fig. 19 Differential Installation

DIFFERENTIAL INSTALLATION (1) Position Spreader W–129–B with the tool dowel pins seated in the locating holes (Fig. 17). Install the hold down clamps and tighten the tool turnbuckle finger–tight. (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. 17) 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. (3) Separate the housing enough to install the case in the housing. Measure the distance with the dial indicator (Fig. 17). (4) Remove the dial indicator. (5) Install differential and outboard shim/spacer (selected thickness) in housing. (6) Install case in the housing. Tap the differential case to ensure the bearings are fully seated (Fig. 19). Remove the spreader. (7) Install the bearing caps at their original locations (Fig. 20). Tighten the bearing cap bolts to 77 N·m (57 ft. lbs.) torque.

DIFFERENTIAL SIDE BEARINGS REMOVAL (1) Remove Differential case from axle housing. (2) Remove the bearings from the differential case with Press 938, and Adapter 1130 (Fig. 21).

Fig. 20 Differential Bearing Cap Reference Letters DIFFERENTIAL SIDE BEARING INSTALLATION If ring and pinion gears have been replaced, verify differential side bearing preload and gear mesh backlash. (1) Using tool C-4340 with handle C-4171, install differential side bearings (Fig. 22). (2) Install differential in axle housing.

RING GEAR The ring and pinion gears are service in a matched set. Do not replace the ring gear with replacing the pinion gear. Refer to Pinion Gear removal and installation paragraph in this section for proper procedure.

REMOVAL (1) Remove differential from axle housing.


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1996 jeep grand cherokee service repair manual  
1996 jeep grand cherokee service repair manual  
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