1990-2004 Pontiac Grand Am and Oldsmobile Alero Collision Repair Manual – PDF Download

1999 Pontiac Grand Am and Oldsmobile Alero Panel Identification ..................................................... 2-1 Front End Assembly ..................................................... 2-3 Front Wheelhouse Assembly ....................................... 2-4 Front Lower Rail Assembly ......................................... 2-7 Door Frame Opening ..................................................2-17 Roof Panel ................................................................... 2-22 Quarter Panel ..............................................................2-24 Rear Wheelhouse ........................................................2-28 Rear Floor Assembly ..................................................2-31 Rear Rails ..................................................................... 2-35 Rear End Panel Assembly ........................................... 2-36 Body Dimensions ........................................................2-37

Coupe white

Thermoplastic Olefin

High-Strength Low-Alloy Steel

Two-Sided Galvanized Steel

Panel Identification

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-1

white

2-2

Thermoplastic Olefin

High-Strength Low-Alloy Steel

Two-Sided Galvanized Steel

Sedan

Panel Identification

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Front End Assembly The front-end structure consists of six resistance-welded components. The upper tie bar and upper reinforcement panel are serviced as individual components. The brace, (front-end lower structure) includes rail reinforcement gussets, which provide cross-car alignment of the service assembly. Left and right impact bar brackets are serviced separately and must be installed using three-dimensional coordinates (Fig.␣ 2.1).

— REMOVE OR DISCONNECT —

1 2 3 4

5

Remove all related panels and components.

Visually inspect and restore as much of the damage as possible to factory specifications.

Remove sealers and anti-corrosion materials as necessary.

Locate, mark and drill out all factory welds as necessary. Note the number of welds for installation of the service panels.

Remove the damaged panels in the upper tie bar assembly and the front end lower brace, as necessary.

— INSTALL OR CONNECT —

1 2

3

4

Prepare mating surfaces and check for proper fit of the service panels.

On the service panels, drill 8mm (5/16) plug weld holes as necessary in the locations noted from the original assembly.

Notice: If original components are damaged beyond recognition, place plug weld holes every 40mm (1-1/2) inches apart.

Position the service panels, check fit using body dimensions, and plug weld accordingly with frequent measurements to ensure proper fit.

Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

5 6

Apply approved anti-corrosion primer Apply sealers and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

Notice: Upper tie-bar service parts do not have mounting locations for (3) center latch-support holes. Use threaded inserts such as Riv-nuts, available through KentMoore tools (Riv-nut Kit P/N J␣ 42151-8MS).

7

Reinstall all related panels and components.

Fig.␣ 2.1 — Front end structure

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-3

Front Wheelhouse Assembly

Fig.␣ 2.2 — Wheelhouse service assembly

The left and right front wheelhousings are available as complete assemblies (Fig.␣ 2.2).

Additionally, the front portion of the aprons and upper rail can be ordered and serviced as a partial assembly (Fig.␣ 2.3). Strut mounting holes are pre-drilled in the service assemblies. The front wheelhouse assembly is serviced without the form and pierced fender mounting locations.

When replacing as an assembly, technicians must three-dimensionally locate fender-mounting holes and use threaded inserts for fender bolts and body shims to achieve correct height (Fig.␣ 2.4). (Riv-nuts with crimping tool are available from Kent-Moore tools: Riv-nut Kit, P/N J42151-8MS).

Sectioning procedures have been developed to simplify wheelhouse repairs. Use the following guidelines to determine whether wheelhouse can be sectioned or should be replaced at factory seams.

Fig.␣ 2.3 — Front assembly also available

,,, Riv-nuts

Fig.␣ 2.4 — Use threaded inserts at fender mounting locations

2-4

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Front Wheelhouse Assembly

Wheelhouse Sectioning

4

At wheelhouse to cowl panel joint, measure forward 75mm (3 inches). Mark a vertical line from strut cap to frame rail (do not cut into strut cap). Cut the wheelhouse along this line, from rail up to strut cap (Fig.␣ 2.5). This will provide an overlap flange for welding the service part to the original wheelhouse, without welding directly to the cowl panel.

Notice: Drill through strut cap welds to locate areas to be re-welded at cowl panel.

5

Locate, mark and drill out the factory welds, which attach the wheelhouse assembly to the cowl panel, radiator support and lower front rails.

Remove the damaged wheelhouse assembly.

Notice: Inspect the cowl panel for damage where the wheelhouse is attached. If the panels have been separated, it will be necessary to repair the cowl panel and replace the wheelhouse at factory seams. If panels have not been separated and there is no damage in this location, the wheelhouse can be serviced as follows.

— REMOVE OR DISCONNECT —

1 2 3

Remove all related panels and components.

Visually inspect and restore as much of the damage as possible to factory specifications.

Remove all sealers and anti-corrosion materials as necessary.

6

Fig.␣ 2.5 — Create weld flange from original panel

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-5

Front Wheelhouse Assembly

— INSTALL OR CONNECT —

1 2 3

4

5 Fig.␣ 2.6 — Trim weld flange from service assembly

6

Clean and prepare surfaces to be welded.

Trim and discard tab off service part which is normally welded to the cowl panel (Fig.␣ 2.6) Drill 8mm (5/16-inch) holes for plug welding in the locations noted from the original assembly.

Drill six holes for plug welding every 40mm (1-1/2 inches) along the overlap which attaches service part to flange remaining from original assembly. (Fig.␣ 2.7) Check the position of the wheelhouse assembly using three-dimensional measuring equipment and plug weld accordingly. Install one weld in the tab from cowl to strut cap.

(Fig.␣ 2.8) Notice: The welds which attach the strut cap to the cowl can be installed from the cowl plenum side of the joint (Fig.␣ 2.8).

Clean and prepare all welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

7

Fig.␣ 2.7 — Drill 8mm (5/15 inch) holes along overlap

Locate and drill 2 fender-mounting holes in new wheelhouse using three-dimensional measuring equipment.

8 Apply approved anti-corrosion primer.

9 Apply sealers and sound deadeners and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

10 Install threaded inserts at fender mounting locations. (Kent-Moore tools: Riv-nut Kit P/N J␣ 42151-MS). Reuse original fasteners or equivalent.

11 Install all related panels and components.

Cowl plenum

Fig.␣ 2.8 — Weld plenum to strut cap from plenum side

2-6

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Wheelhouse

Front Lower Rail Assembly Replacement of the engine compartment lower rail assemblies has been improved on the Grand Am/Alero through the use of a sub-assembly service part. The lower rail service part comes complete with all brackets and reinforcements (Fig.␣ 2.9). When sectioning, order the entire assembly and extract the necessary parts (Fig.␣ 2.10).

Fig.␣ 2.9 — Left side service assembly

Fig.␣ 2.10 — Extract parts for sectioning

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-7

Front Lower Rail Assembly

Lower Rail Sectioning Sectioning procedures have been developed to help simplify repair of the lower rails, provided the majority of damage can be returned to factory specifications. This allows technicians to repair the damaged front section without having to make a complete rail replacement. Sectioning of the lower rail does not require removal of the powertrain.

Important: Damage to the front lower rails must be limited to the portion of the rail forward of the sectioning joint, if damage exceeds the forward portion, complete replacement of the rail is recommended.

(See complete rail replacement procedures.)

Notice: The lower rail sectioning cut lines vary from left to right. Be sure to use the correct procedure. (Fig.â?Ł 2.11)

Left rail, inner

Right rail, inner

Right rail, outer

Fig.� 2.11 — Unique rails, unique repair procedures left to right

2-8

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Front Lower Rail Assembly

LEFT - FRONT LOWER RAIL SECTIONING — REMOVE OR DISCONNECT —

1 2 3 4

5

6 7

8

Remove all related panels and components including left front cradle bolt.

Visually inspect and restore as much of the damage as possible to factory specifications.

Remove all sealers and anti-corrosion materials as necessary.

Apply 25mm (1 inch) wide tape on the lower rail outer panel following the contour of the cowl (Fig.␣ 2.12). Cut the outer panel along the forward edge of the tape. This will provide an overlap tab for welding the service part to the original rail without welding directly to the cowl panel.

Drill out all factory welds attaching the outer panel to the rail inner panel, be sure not to drill through the inner panel.

Notice: Welds on engine cradle mounting bracket must also be drilled out to remove outer panel.

Remove the rail outer panel.

Locate the 16 x 35 slot on the in-board side of the rail (Fig.␣ 2.13). Using the hole as a guide, mark a line on all three sides of the rail.

Cut the rail along the marked line and remove the damaged portion of the rail.

Fig.␣ 2.12 — Cut the outer panel along forward edge of tape

Fig.␣ 2.13 — Mark a line on the damaged rail

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-9

Front Lower Rail Assembly

PREPARING SERVICE PART FOR INSTALLATION

3

— INSTALL OR CONNECT —

1

2

Locate and drill out factory welds attaching the outer panel to the inner panel on the service part. Drill through one layer ONLY at the front half of the rail.

Notice: Welds on engine cradle mounting bracket must also be drilled out to remove outer panel.

Separate inner from outer rail using an air chisel. Remove the outer panel and set aside.

4 5

6

On the left inner rail service part, mark a line around the panel 30mm (1-1/4 inch) rearward of the 16 x 35 hole on the inner rail. Using the hole as a guide, mark a line around the rail (Fig.␣ 2.14).

Cut the service part along the marked line and discard the unused section.

On the sectioned service part, cut a 2mm (1/8 inch) gap approximately 30mm (1-1/4 inch) deep along the corners of the inner rail to create tabs (Fig.␣ 2.15).

Step the tabs inward to allow the service part section to fit inside the original rail (Fig.␣ 2.15).

30mm

Fig.␣ 2.14 — Left rail service part, add 30mm for weld tabs

1. Cut Corners

2. Step tabs inward

Fig.␣ 2.15 — Cut corners and step tabs inward on service part

2-10

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Front Lower Rail Assembly

7

8

9

Drill 5 holes for plug welding along the overlap, approximately 13mm (1/2 inch) from the sectioning cut (Fig.␣ 2.16).

Position the modified service part inside the original rail align using three-dimensional measuring equipment.

On rail outer panel, trim off tab that attaches to cowl panel. Drill three 8mm (5/16 inch) plug weld holes along overlap.

Notice: Be certain the engine cradle mounting location is in the proper position. Align and hand tighten bolt.

Important: When stitch welding, make 25mm (1 inch) welds along the seam with 25mm (1 inch) gaps between. Then go back and complete the stitch weld along the seam.

10 Position the outer panel, check for proper fit and alignment.

11 Stitch weld along the entire joint. Plug weld all holes drilled during the removal process including holes drilled along overlapped areas (Fig.␣ 2.17).

12 Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

13 Apply approved anti-corrosion primer.

14 Apply sealers and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

15 Install all related panels and components.

Fig.␣ 2.16 — Drill 8mm (5/16 inch) holes for plug welding

Fig.␣ 2.17 — Plug welds and stitch welds completed

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-11

Front Lower Rail Assembly

RIGHT - FRONT LOWER RAIL SECTIONING

5

— REMOVE OR DISCONNECT —

1 2 3 4

Remove all related panels and components.

Visually inspect and restore as much of the damage as possible to factory specifications.

Remove all sealers and anti-corrosion materials as necessary.

Apply 25mm (1 inch) wide tape on the lower rail outer panel following the contour of the cowl. Cut the outer panel along the forward edge of the tape (refer to Fig.␣ 2.12). This will provide an overlap for welding the service part to the original rail, without welding directly to the cowl panel.

6

7

Drill out all the factory welds attaching the outer panel to the rail inner panel, be sure not to drill through the inner panel. Remove the rail outer panel.

Measure 75mm (3 inches) forward of the engine mount brace located inside the rail and mark a line (Fig.␣ 2.18). Drill a 1/8 inch hole on the line. Using the hole as a guide, mark a line around the outside of the rail.

Cut the rail along the marked line and remove the damaged portion of the rail.

75mm

Right rail, inner

Right rail, outer

Fig.␣ 2.18 — Remove outer panel and measure damaged inner rail

2-12

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Front Lower Rail Assembly

3

PREPARING SERVICE PART FOR INSTALLATION — INSTALL OR CONNECT —

1

2

Locate and drill out factory welds attaching the outer panel to the inner panel on the service part. Drill through one layer ONLY at the front half of the rail.

Notice: Welds on engine cradle mounting bracket must also be drilled out to remove outer panel.

Separate inner from outer rail using an air chisel. Remove the outer panel and trim off the rear edge that welds to the cowl panel.

4 5

6

On the right side rail, measure 45mm (1-3/4␣ inches) forward of the engine mount brace (Fig.␣ 2.19), notice this is 30mm (1-1/4 inches) less than the original sectioning cut.

Drill a 1/8- inch hole on the line. Using the hole as a guide, mark a line around the rail.

Cut the service part along the marked line and discard the unused section.

On the sectioned service part, cut a 2mm (1/8 inch) gap approximately 30mm (1-1/4 inch) deep along the corners of the inner rail to create tabs (Fig.␣ 2.20).

Step the tabs inward to allow the service part section to fit inside the original rail (Fig.␣ 2.20).

Right rail, inner 45mm

FRT

Right rail, outer

Fig.␣ 2.19 — Remove outer panel to measure inner rail on service part

1. Cut Corners

FRT 2. Step tabs inward

Fig.␣ 2.20 — Cut corners and step tabs inward on service part

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-13

Front Lower Rail Assembly

7

8

9

Drill 5 holes for plug welding along the overlap, approximately 13mm (1/2 inch) from the sectioning cut (Fig. 2.21) Position the modified service part inside the original rail using three-dimensional measuring equipment.

Notice: Be certain the engine cradle mounting location is in the proper position. Align and hand tighten bolt.

10 Position the outer panel, check for proper fit and alignment.

11 Stitch weld along the entire joint. Plug weld all holes drilled during the removal process (Fig.␣ 2.22).

12 Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

Important: When stitch welding, make 25mm (1 inch) welds along the seam with 25mm (1 inch) gaps between. Then go back and complete the stitch weld.

13 Apply approved anti-corrosion primer.

14 Apply sealers and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

15 Install all related panels and components.

Drill 3 holes in the rail outer panel in front of the cowl.

Fig.␣ 2.21 — Drill 8mm (5/16 inch) holes for plug welding

Fig.␣ 2.22 — Plug welds and stitch weld completed

2-14

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Front Lower Rail Assembly

FRONT LOWER RAIL REPLACEMENT — REMOVE OR DISCONNECT —

1 2 3 4 5

6

Remove all related panels and components.

Visually inspect and restore as much of the damage as possible to factory specifications.

Remove sealers, sound deadeners and anti-corrosion materials as necessary.

Using an air chisel, remove the rear engine mount.

Locate and drill out resistance welds in torque box panel (Fig.␣ 2.23). Drill through one layer of metal ONLY. From underside of vehicle, locate welds that secure the rail to the floorpan. Using a

1/8-inch drill bit, drill through floor to mark welds for removal.

7 Separate the floor pan reinforcement vertical flange from inside the lower rail. Care must be taken to not damage the flange.

8 Drill out factory welds along the lower flange on the floor pan reinforcement and at the wheelhouse. Note that the flanges overlap the rails.

9 From inside the vehicle, use an 8mm (5/16 inch) drill bit to drill through the floor pan and the reinforcement inside the vehicle (Fig␣ 2.24).

10 Remove the damaged rail.

Fig.␣ 2.23 — Drill through rail in torque box to locate welds inside vehicle

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-15

Front Lower Rail Assembly

— INSTALL OR CONNECT —

1

2

3

Prepare mating surfaces and check for proper fit of the new rail. Apply suitable weld-through primer.

Position the new rail in place and check for proper alignment using three-dimensional measuring equipment.

With the new rail in place, plug weld all the holes created from the removal process. In the areas the floor inner panel does not contact the floor pan, use a ball- peen

4

5 6

7

hammer to flatten inner panel against floor pan. Plug weld floor to new rail in remaining areas.

Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

Apply approved anti-corrosion primer.

Apply sealers and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

Install all related panels and components.

Fig.␣ 2.24 — Drill from inside vehicle at pilot hole locations using an 8mm (5/16 inch) drill bit

2-16

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Door Frame Opening The side door frame openings feature a unique modular build sub-assembly design to improve manufacturing quality. They are composed of numerous individual components that are pre-assembled and then attached to the vehicle as a single unit.

The door frame can be replaced as a complete assembly or various segments of it can be sectioned, which is usually much faster and more cost effective. However, there are some key structural areas where sectioning should not take place (Fig.␣ 2.25). Since left and right door frame openings are available as complete assemblies, service parts for sectioning must be cut from the complete assembly and modified as necessary.

SECTIONING SHOULD NOT TAKE PLACE IN SHADED AREAS

Fig.␣ 2.25 — Coupe and Sedan side door frames

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-17

Door Frame Opening

Door Frame Opening Full Replacement

3

— REMOVE OR DISCONNECT —

1

2 3 4

5

Remove all related panels and components including the roof panel, upper outer rail reinforcement and, on coupe models only, the quarter panel.

Visually inspect and restore as much of the damage as possible to factory specifications.

Remove sealers, sound deadeners and anticorrosion materials as necessary.

Locate, mark and drill out all factory welds.

Note the number of welds for installation of the service assembly.

Remove the damaged doorframe opening.

— INSTALL OR CONNECT —

1

2

Prepare mating surfaces and check for proper fit of the door frame opening service assembly.

On the service assembly, drill 8mm (5/16-inch) plug weld holes as necessary in the locations noted from the original assembly.

Notice: In any area damaged beyond recognition, space plug weld holes every 40mm (1-1/2 inches) apart.

4

5

6 7

8

9

Position the service assembly, check fit using body dimension and plug weld accordingly with frequent measurements to ensure proper fit.

Inject expandable foam into the “A” Pillar through the bottom interior trim-mounting hole. This helps reduce noise in the passenger compartment.

Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

Apply approved anti-corrosion primer.

Apply a full-bodied caulk along the surface of the baffle to ensure a proper seal with the inner cowl plenum (Fig.␣ 2.27).

Apply sealers and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations Reinstall all related panels and components.

Do not plug drain slot

Fig.␣ 2.27 — Apply sealer along inner cowl plenum

Fig.␣ 2.26 — Remove upper outer rail reinforcement

2-18

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Door Frame Opening

General Sectioning Procedures

— REMOVE OR DISCONNECT —

When sectioning areas other than the hinge pillar, a 100mm (4 inch) backing plate must be used behind the joint to ensure a solid and secure weld in areas where there is no inner reinforcement. Backing plates can usually be cut from the unused portion of the service part or an undamaged section of the doorframe opening.

1 2

Notice: There are some key reinforcements that are to be replaced at factory seams only (Fig. 2.28). Sectioning these panels may compromise the structural integrity of the vehicle.

The rocker panel can also be replaced in its entirety when the quarter panel has been removed.

3 4

5

6

Remove all related panels and components.

Visually inspect and restore as much of the damage as possible to factory specification.

Remove sealers, sound deadeners and anticorrosion materials as necessary.

Cut the doorframe opening where it is to be sectioned. Do not damage any inner panels or reinforcements.

Locate, mark and drill out all necessary factory welds. Note the number of welds for installation of the service part.

Remove the damaged section of the doorframe opening.

Reinforcements are replaced at factory seams only

Fig.␣ 2.28 — Door frame reinforcements are part of the service assemblies

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-19

Door Frame Opening

— INSTALL OR CONNECT —

1

2

Cut the service part to match the undamaged section of the door frame opening and remove unused portion of the service part.

Cut an appropriate-sized backing plate from the unused portion of the service part or undamaged section of the doorframe opening. Modify the backing plate as necessary so that it will fit behind the sectioning joint (Fig.␣ 2.29).

Gap = one and one-half times the thickness of the metal

100mm (4 in) Backing Plate

100mm

50mm

100mm 100mm

50mm

100mm

Fig.␣ 2.29 — Door frame sectioning specifications

2-20

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Door Frame Opening

3

Windshield pillar sectioning requires a 50mm (2 inch) backing plate. Section within the recommended areas (Fig. 2.29).

Notice: The striker plate is mounted in a cage that allows some degree of adjustment independent of the outer panel’s. Use body dimensions to ensure the striker mounting location falls within the plate’s range of adjustment

4

Sectioning the rocker panel requires a 100mm (4 inch) backing plate for reinforcement (Fig. 2.29). Section within the recommended area.

On the service part, drill 8mm (5/16-inch) plug weld holes as necessary in the locations noted from the original section. Also, drill plug weld holes along the sectioning cut on both the service part and the remaining original part. These will be used to weld the panel to the backing plate.

Prepare mating surfaces and slide the backing plates halfway under the sectioning cuts on the vehicle and plug weld in place.

5

6

7

Position the service part, allowing it to overlap the exposed portion of the backing plates. Check fit using body dimensions and plug weld accordingly with frequent measurements to ensure proper fit.

8 Stitch weld along the sectioning joints. Make 25mm (1 inch) welds along the seam with 25mm (1 inch) gaps between. Then go back and complete the stitch weld. This will create a solid joint with minimal heat distortion.

9 Complete all other welds as necessary.

10 Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

11 Apply approved anti-corrosion primer 12 Apply sealers and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

13 Reinstall all related panels and components.

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-21

Roof Panel The roof panel is made of mild steel and welded to the steel roof structure, including the outer panel and the inner reinforcements. The roof panel is serviced as a “skin” with no reinforcements, only sound-soak patches pre-installed for efficient installation.(Fig.␣ 2.30) The roof panel must be drilled to remove the outer panel and inner reinforcements for servicing.

Notice: The headliner, windshield and backglass must be removed prior to the removal of the roof assembly. Protect the interior of the vehicle. Use care when working near adjacent panels, glass, weatherstrips and moldings.

Important: On vehicles equipped with a sunroof, take care not to damage the drain tubes. The drain tubes are located between the inner and outer windshield pillar.

T FR Pre-installed sound-soak panel

Fig.␣ 2.30 — Coupe roof panel with sunroof opening

2-22

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Roof Panel

— REMOVE OR DISCONNECT —

Silicon Bronze Joint

1

2 3 4 5

6

7 8

Remove all related panels and components necessary to access the welds attaching the roof assembly to the vehicle.

Visually inspect and restore as much of the damage as possible.

Remove sealers and anti-corrosion materials as necessary.

Locate silicon-bronze joints which attach roof panel to quarter panels (Fig.␣ 2.31).

Cut through the roof panel just above the left and right silicon-bronze joints using a die-grinder or equivalent tool (Fig.␣ 2.32).

Locate, mark and drill out all factory welds.

Note the number and location of welds for installation of the service assembly.

Remove the damaged roof panel assembly.

Grind off silicon-bronze weld and remove remaining roof panel tabs.

— INSTALL OR CONNECT —

Fig.␣ 2.31 — Locate roof seam at quarter panel

1 2 3 4

DO NOT CUT SAIL PANEL REINFORCEMENT. CUT ROOF PANEL ONLY

Clean and prepare the mating surfaces as necessary.

Position the roof panel on the vehicle. Check fit and alignment.

When the service assembly is correctly positioned, plug weld accordingly.

MIG stitch weld the quarter panel to roof joints at factory seams.

Important: Make 25mm (1 inch) welds along the seam with 25mm (1 inch) gaps between. Then go back and complete the stitch weld. This will create a solid joint with minimal heat distortion.

5

Clean and prepare all welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

6

Apply approved anti-corrosion primer.

Notice: The windshield and bonding area should be a primer surface ONLY and not an aftermarket, top-coated (paint or color-coated) surface. Refer to Bulletin #43-10-48 for more detailed information.

7

Apply sealers and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

Install all related panels and components.

8 Fig.␣ 2.32 — Rough cut roof panel above factory seam

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-23

Quarter Panel The quarter panel is a service assembly that includes the gutter, lock-striker cagenut and an extension panel for the taillamp pocket (tail lamp pocket is serviced separately). Replacement of the quarter panel requires removal of the back light and quarter glass on coupe models. On both the coupe and sedan models, the quarter

panel is attached to the roof panel by a silicon-bronze welded joint. To maintain the integrity of this joint, sectioning of the quarter panel at sail panel will be performed 100mm (4␣ inches) below this joint where roof overlaps quarter panel (Fig. 2.33).

SEDAN

Taillamp pockets serviced separately

COUPE Fig.␣ 2.33 — Quarter panel service assemblies

2-24

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Quarter Panel

Coupe Quarter Panel Service Procedure

5

At B-Pillar location on outer panel only, measure distance between lower 2 trim holes. Scribe a line at half the distance between the 2 holes. This is the recommended sectioning point (Fig.␣ 2.34).

Notice: Do not cut into inner reinforcement.

6

At scribed line, cut quarter panel ONLY. Locate, mark and drill out the factory welds.

Note the location and number of welds.

Remove damaged quarter panel.

Remove majority of baffle material in sail panel and along rocker panel.

— REMOVE OR DISCONNECT —

1 2 3 4

Visually inspect and restore as much of the damage as possible to factory specifications.

Remove all related panels and components, including the side and back glass.

Remove sealers, sound deadeners and anti-corrosion materials as necessary.

Locate silicone-bronze seam at roof/quarterpanel overlap. Measure down 100mm from pinch weld flange at side and rear window (door frame) locations (Fig.␣ 2.34). Mark cut line.

100mm

7 8

Measure equal distance between trim holes

Fig.␣ 2.34 — Locating coupe quarter panel sectioning locations

100mm

Fig.␣ 2.35 — Measure and mark 100mm down from silicon bronze joint

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-25

Quarter Panel

PREPARING SERVICE PANEL FOR INSTALLATION — INSTALL OR CONNECT —

1

2

3

4

5

6

7 8

At the sail panel, measure and mark a line 100mm from step at top edge of service part (Fig.␣ 2.35).

At B-Pillar location on outer panel only, measure distance between lower 2 trim holes. Scribe a line at half the distance between the 2 holes.

This is the recommended sectioning point (see Fig. 2.34).

Cut along line to trim service part and create a 100mm backing plate. Remove the flange on each side of backing plate so that it will fit behind the sectioning joint.

Drill 8mm (5/16) plug weld holes as necessary in the locations noted from the original panel. Drill plug weld holes along the sectioning areas of the service part and original panel. These holes should be located approximately 13mm (1/2␣ inch) from the edge of the cuts (Fig.␣ 2.36).

Prepare the mating surfaces. Position and secure both backing plates with half of the backing plate exposed at each joint. Position the service part to overlap the backing plates and butt up to the original panel (Fig. 2.37). Check for proper fit and alignment.

Notice: Leave a gap of one and one half times the thickness of the metal at the sectioning joint.

Fig.␣ 2.36 — Drill 8mm 5/16 plug weld holes along overlap

Important: Care must be taken to ensure that the fuel filler neck is properly sealed when replacing the right side quarter panel. Use SPO Sealing strip (P/N 12399117) between the quarter panel and the fuel filler neck. Install according to provided instruction sheet.

Plug weld accordingly. Stitch weld along the entire sectioning joint. Make 25mm (1 inch) welds along the seam with 25mm gaps between them. Go back and complete the stitch weld.

This will create a solid joint with minimal heat distortion.

Plug weld all other areas as noted from the original panel.

Clean and prepare all welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 Refinish Manual for recommended products.

9 Apply approved anti-corrosion primer.

10 Apply body sealers and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

11 Install all related panels and components.

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100mm

50mm

Fig.␣ 2.37 — Use the correct size backing plates when installing new panel

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Quarter Panel

Sedan Quarter Panel Service Procedure — REMOVE OR DISCONNECT —

1 2 3 4

5

6

Remove all related panels and components, including the back glass.

Visually inspect and restore as much of the damage as possible to factory specifications.

Remove sealers and corrosion protection materials as necessary.

Note the size of the service part and locate the sectioning joint at the “sail panel.” Mark a line 100mm below the silicon bronze joint and cut (Fig.␣ 2.39).

Locate, mark and drill out all factory welds.

Note the number and location of welds for installation of the service assembly.

Remove the damaged quarter panel.

100mm

— INSTALL OR CONNECT —

1 2

3

4

5

6 7

Prepare the mating surfaces as necessary.

Temporarily position the service panel on vehicle. Trim the original panel to leave a gap of one and one half times the thickness of the metal at the sectioning joint Cut 100mm (4-inch) piece from the original quarter panel for backing plates. Remove the flange on each side of the backing plates so that they will fit behind the sectioning joints.

Drill 8mm (5/16-inch) plug weld holes as necessary in the locations noted from the original panel. Also drill plug weld holes along the sectioned area of the service part.

These should be located approximately 25mm (1 inch) from the edge of the cuts (Fig.␣ 2.39).

Prepare the mating surfaces. Position the service part to overlap the backing plate and butt up to the original panel (Fig. 2.40).

Notice: Leave a gap of one and one half times the thickness of the metal at the sectioning joint.

Plug weld all other areas as noted from the original panel.

Clean and prepare all welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

8 9

Fig.␣ 2.38 — Measure 100mm below silicon bronze joint

Apply approved anti-corrosion primer Apply sealers, sound deadeners and corrosion protection materials.

10 Refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendation.

11 Install all related panels and components.

Fig.␣ 2.39 — Drill 8mm (5/16 inch) holes for plug welding Fig.␣ 2.40 — Use 100mm (4 inch) backing plate

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-27

Rear Wheelhouse The sedan outer rear wheelhouse (Figs. 2.41) can be replaced at factory seams. Both models have a beltline reinforcement that overlaps a portion of the wheelhouses. Remove the reinforcement on sedan models according to recommended procedures. On coupe models, templates have been developed to ensure proper wheelhouse installation on coupe models.

Sedan — REMOVE OR DISCONNECT —

1 2 3

4 5

Remove all related panels and components including the back glass.

From inside of vehicle, pull back and protect wiring along inner wheelhouse.

Locate and drill out six welds securing beltline reinforcement to quarter inner assembly (Fig.␣ 2.42) Notice: Drill through one layer only.

Fig.␣ 2.41 — Replacement wheelhouse (coupe/sedan)

Locate and drill out welds at factory seams along perimeter of wheelhouse flange.

Remove damaged wheelhouse panel.

— INSTALL OR CONNECT —

1 2 3 4

On service part, drill 8mm (5/16-inch) holes every 40mm (1-1/2 inches).

Prepare mating surfaces.

Apply suitable weld-through primer.

Position service part. Check for proper fit.

Notice: Outer wheelhouse positioning may require dry-fitting of quarter outer panel.

5

Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

6 7

Apply approved anti-corrosion primer.

Apply sealers and sound deadener materials and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

Install related panels and components.

8

2-28

Fig.␣ 2.42 — Remove beltline reinforcement (SEDAN ONLY)

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Rear Wheelhouse

Outer Rear Wheelhouse

— REMOVE OR DISCONNECT —

Notice: It is recommended that the service part be prepared before removing the damaged panel from the vehicle.

1 2 3

Coupe PREPARING THE SERVICE PART FOR INSTALLATION 1 Align the appropriate template along the service part contour lines, per template instructions.

2 Cut service part as indicated on template to ensure proper fit of service part.

3 Trim leading edge of service part to allow flush fit with rocker panel (Fig.␣ 2.44).

4 Remove the excess portion of the wheelhouse.

4

5 6

7 8

Remove all related panels and components Visually inspect and restore as much of the damage as possible to factory specifications.

Remove sealers and sound deadeners as necessary.

Apply 25mm (1 inch) tape along perimeter of beltline reinforcement where it contacts outer wheelhouse.

Cut along outer (Fig. 2.44) edge of tape to form mating flange.

Apply tape to lower front portion of wheelhouse, parallel to rocker panel edge, cut along top edge of tape from outer lip of wheelhouse to valley (see Fig.␣ 2.44), creating a flange for reattachment of wheelhouse part at rocker panel.

Cut along radius of wheelhouse (Fig. 2.45).

Remove the damaged wheelhouse.

Beltline Reinforcement

Fig.␣ 2.43 — Modify wheelhouse service part (COUPE ONLY)

Fig.␣ 2.44 — Apply tape as indicated to leave a portion of the original wheelhouse for efficient installation of the service panel

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-29

Rear Wheelhouse

— INSTALL OR CONNECT —

1

2

3

4

5

Fig.␣ 2.45 — Separate wheelhouse from quarter inner assembly (leave weld flange in place)

Remove weld flange on remaining portion of original wheelhouse (at rocker panel) to ensure proper fit of service part.

Temporarily install service part over beltline reinforcement flange and inside of original wheelhouse (Fig. 2.46).

On the service part, drill 8mm (5/16 inch) plug weld holes every 40mm (1-1/2 inches along perimeter of entire service part.

(Fig.␣ 2.47) Drill 4 holes on edge where service part mates to rocker panel.

Prepare the mating surfaces and position the service part. Apply suitable weld-through primer.

Check for proper fit and plug weld accordingly. Use care to not warp or distort the metal.

Notice: Outer wheelhouse positioning may require dry-fitting of quarter outer panel.

6

Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

7 8

Apply approved anti-corrosion primer.

Apply sealers and sound deadeners as necessary. Do not combine paint systems.

Refer to paint manufacturer’s recommendations.

Install all related panels and components.

9

Over

Inside

Fig.␣ 2.46 — Install modified wheelhouse

Fig.␣ 2.47 — Service part modified (COUPE ONLY)

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1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Rear Floor Assembly The rear floor is sold as a complete assembly including rear rails, crossmembers and rear extension; or sold separately as floor pan “skin” with exhaust heat shield only. (Fig.␣ 2.48)

Rail extensions

With the floor pan removed, drill out and replace rear frame rail extensions at factory seams. Use 8mm (5/16 inch) plug welds to reinstall the replacement rail extensions.

Fig.␣ 2.48 — Floor pan “skin” and rail extensions are serviced

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-31

Rear Floor Assembly

Rear Floor Panel Partial Replacement — REMOVE OR DISCONNECT —

1 2 3 4

Remove all related panels and components, including fuel tank.

Visually inspect and restore as much of the damage as possible.

Remove sealers, sound deadeners and anti-corrosion materials as necessary.

Locate factory seam at front edge of crossbar, rearward of seat back. Locate, mark and drill through one layer only, all

5 6

7

factory welds which secure floor to rails.

Note the number and location of welds for installation of the floor service panel (Fig. 2.49).

Drill completely through welds that attach the floorpan to the inner wheelhouse.

Remove both inner wheelhouse braces.

Identify weld locations and drill through one layer of metal only.

Remove the damaged floor section.

Important: On pan only re-install, wheelhouse flange must be bent up on service part to accommodate welds.

Fig.␣ 2.49 — Floor pan weld joint on vehicle

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1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Rear Floor Assembly

— INSTALL OR CONNECT —

1 2

Prepare mating surfaces with suitable weld-through primer.

Drill 8mm (5/16-inch) plug weld holes as necessary in the locations noted from the original floor.

Notice: In any area damaged beyond recognition, space plug weld holes every 40mm (1-1/2 inches) apart.

Important: Sound deadeners along the inner wheelhouse must be removed prior to welding new panels in place 3

4 5

Re-install both wheelhouse braces (Fig. 2.50).

Clean and prepare all welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

6 7

Apply approved anti-corrosion primer.

Apply body sealers and refinish as necessary.

Do not combine paint systems. Refer to paint manufacturer’s recommendations.

Install all related panels and components.

8

Position the service floor pan, check for proper fit using three-dimensional measuring and plug weld accordingly.

Fig.␣ 2.50 — Reinstall internal floor braces (2 per side)

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-33

Rear Floor Assembly

FLOOR PAN ASSEMBLY

— INSTALL OR CONNECT —

The floor pan assembly comes complete including lower rails, crossbar, rear floor extension and various other components.

(Fig.␣ 2.51)

1

Prepare mating surfaces with suitable weld-through primer.

Notice: In any area damaged beyond recognition, space plug weld holes every 40mm (1-1/2 inches) apart.

Notice: One side inner and outer wheelhouses must be removed when replacing entire sub-assembly.

2

1 2

3

Drill 8mm (5/16-inch) plug weld holes along all mating surfaces except where the floor mates to each wheelhouse.

Position the service floorpan. Check for proper fit using three-dimensional measurements.

Clean and prepare all welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

— REMOVE OR DISCONNECT —

3 4

Remove all related panels and components.

Visually inspect and restore as much of the damage as possible.

Remove sealers, sound deadeners and anti-corrosion materials as necessary.

Remove 4 inner reinforcements ( 2-dynamic side impact braces-front; 2- floor pan braces-rear) to access spot welds (Fig 2.52).

Notice: If these parts are damaged they must be ordered separately.

4

5 6

7

Apply approved anti-corrosion primer to all bare metal surfaces.

Apply body sealers and refinish as necessary.

Do not combine paint systems. Refer to paint manufacturer’s recommendations.

Reinstall all related components.

Fig.␣ 2.51 — Floor pan assembly

Fig.␣ 2.52 — Remove all four internal braces to locate hidden welds

2-34

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Rear Rails The left and right rear rails are available as complete sub-assemblies and can be replaced in their entirety similar to past model vehicles. Each consists of an outer panel, two inner reinforcements and all necessary component mounting brackets. The outer panel and rear mounting brackets are also available separately.

When replacing a rail in its entirety, the weld flange that mates with the wheelhouse must be bent upwards. The service assembly is supplied with this flange in a horizontal position. (Fig. 2.53)

The rear rail can be removed by drilling out all factory welds at the floor pan. When doing so, the outboard flange at the forward end of the rail overlapping the rocker interior panel must be bent upward. The bottom flange of the crossbar must be bent downward.

Notice: Remove the floor and wheelhouse braces at factory seams to access additional lower rail welds. Reinstall upon completion (see Fig. 2.52).

The rear rail can then be separated from the vehicle.

Service assembly supplied with horizontal wheelhouse flange

Service assembly with wheelhouse flange bent upwards for installation

Fig.� 2.53 — Modify weld flange if ordering and installing entire rear rail only

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-35

Rear End Panel Assembly The rear end panel is supplied as a complete assembly consisting of three inner reinforcements and one outer panel. The rear end panel on the coupe has a single inner reinforcement.

Taillight mounting panels, which attach to the outside corners of the rear end panel assembly, are available separately. Service for all of these panels is performed at factory seams (Fig.␣ 2.54).

— INSTALL OR CONNECT —

— REMOVE OR DISCONNECT —

3

1 2 3 4

5

Remove all related panels and components.

Visually inspect and restore as much of the damage as possible to factory specifications.

Remove sealers, sound deadeners and corrosion materials as necessary.

Locate, mark and drill out all factory welds.

Note the number of welds for installation of the service assembly.

Remove the damaged assembly.

1 2

4

5 6

7

Prepare mating surfaces and check for proper fit o the service assembly.

On the service assembly, drill 8mm (5/16-inch) plug weld holes as necessary in the locations noted from the original assembly. Apply suitable weld-through primer.

Position the service assembly, check fit using body dimensions and plug weld accordingly with frequent measurements to ensure proper fit.

Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM P/N 4901 M-D Refinish Manual for recommended products.

Apply approved anti-corrosion primer.

Apply sealers and refinish as necessary. Do not combine paint systems. Refer to paint manufacturer’s recommendations.

Reinstall all related panels and components.

Fig.␣ 2.54 —

2-36

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

D L: 1250 W: 465 H: 326

C L: 1215 W: 442 H: 326

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair B L: 292 W: 356 H: 243

CL

A L: 0 W: 435 H: 133

O L: 1650 W: 563 H: 400

N L: 2111 W: 430 H: 369

F L: 2126 W: 430 H: 360

H L: 2226 W: 430 H: 371

M L: 2321 W: 433 H: 369

G L: 2163 W: 560 H: 834

ALL DIMENSIONS ARE MEASURED FROM A ZERO LINE, CENTER LINE, AND A COMMON DATUM. ALL DIMENSIONS ARE SYMMETRICAL UNLESS OTHERWISE SPECIFIED.

E L: 506 W: 561 H: 810

L L: 2466 W: 440 H: 375

I L: 2391 W: 440 H: 400

K L: 2733 W: 440 H: 364

J L: 2850 W: 440 H: 400

Body Dimensions

2-37

Body Dimensions

FRONT VIEW P W: 508 H: 416 L: 1364

Q W: 517 H: 474 L: 1364

CL

R W: 517 H: 376 L: 1364

S W: 517 H: 376 L: 1364

REAR VIEW T W: 374 H: 346 L:3013

U W: 508 H: 416 L:3013

CL

V W: 374 H: 346 L:3013

W W: 374 H: 346 L:3013

ALL DIMENSIONS ARE MEASURED FROM A ZERO LINE, CENTER LINE, AND A COMMON DATUM. ALL DIMENSIONS ARE SYMMETRICAL UNLESS OTHERWISE SPECIFIED.

2-38

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

Body Dimensions

1999 Grand Am/Alero Underbody Dimension Hole Size Chart Letter

Feature Size

Usage

A

19mm

gage hole

B

20mm

cradle attach

C

13mm x 19mm

gage slot

D

20mm

cradle attach

E

76mm

center strut cap

F

15mm

rear suspension attach

G

83mm

center strut cap

H

15mm

rear suspension attach

I

19mm

gage hole

J

19mm x 26mm

slot

K

19mm x 26mm

slot

L

19mm

gage hole

M

15mm

rear suspension attach

N

15mm

rear suspension attach

O

19mm

gage hole

P

14mm x19mm slot

front impact bar

Q

14mm

front impact bar

R

14mm x 19mm slot

front impact bar

S

14mm

front impact bar

T

10mm

rear impact bar

U

10mm

rear impact bar

V

10mm

rear impact bar

W

10mm x 18mm slot

rear impact bar

1999 Pontiac Grand Am/Oldsmobile Alero Collision Repair

2-39