For 1990-2009 cars

#### Special Tools

• | J-34826 Hub Nut Socket (36 mm)

• | J-45005 Seal Installer

• | J-45012 Holding Fixture

• | J-45019 Flange and Pinion Cage Remover

### Removal Procedure

1. Raise and support vehicle. Refer to Lifting and Jacking the Vehicle.
2. Remove the floor panel tunnel rear panel. Refer to Floor Panel Tunnel Panel Replacement - Rear.
3. Support the rear drive module (RDM).

Note: Remove only the propeller shaft coupler-to-differential flange bolts. Do NOT remove the coupler from the propeller shaft.

4. Remove the differential carrier bracket-to-frame bolt (3).
5. Remove the propeller shaft coupler-to-differential flange nuts (4), bolts (7), and washers (6).
6. Push the propeller shaft (1) toward the front of the vehicle in order to release the propeller shaft coupler (2) from the differential pinion flange (5).
7. Lower the propeller shaft and the front of the RDM until disconnected.
8. Carefully position the propeller shaft (1) aside and support the propeller shaft using a suitable jack.
9. Install the J-45012 fixture to the flange.
10. While holding the J-45012 fixture , remove the drive pinion nut using the J-34826 socket .
11. Remove the J-45012 fixture .
12. Install the J-45019 remover to the flange.
13. Using the J-45019 remover , remove the flange.
14. Using a flat-bladed tool, remove the drive pinion seal. Take care not to damage any sealing surfaces.

### Installation Procedure

Note: Ensure the pinion bore is free of excess gear oil. Excessive fluid can get trapped behind the new seal's dust shield. The trapped gear oil can get squeezed out when installing the pinion flange and give the illusion of a continued leak.

1. Lubricate the drive pinion flange sealing surface of the drive pinion seal with synthetic gear oil GM P/N 12378514 (Canadian P/N 88901045) or equivalent.
2. Install the drive pinion seal to the J-45005 installer .
3. Using the J-45005 installer , install the pinion seal to the differential.
4. Remove the J-45005 installer .
5. Remove the J-45019 remover .
6. Install the J-45012 fixture .
7. Install the pinion flange to the drive pinion shaft.

Note: The pinion shaft threads and the pinion flange nut must be free of residue and debris prior to application of threadlocker in order to ensure proper adhesion and fastener retention.

8. Prepare the pinion shaft threads and the pinion flange nut for assembly:

8.1. | Thoroughly clean the residue from the pinion shaft threads by using denatured alcohol or equivalent and allow to dry.

8.2. | Thoroughly clean the residue from the pinion flange nut by using denatured alcohol or equivalent and allow to dry.

9. Apply threadlocker GM P/N 12345382 (Canadian P/N 10953489) or equivalent to 2/3 of the threaded length of the pinion shaft threads. Ensure that there are no gaps in the threadlocker along the length of the filled area of the pinion shaft threads.
10. Allow the threadlocker to cure approximately 10 minutes before installation.

Caution: Refer to Fastener Caution in the Preface section.

11. Install the drive pinion flange nut to the pinion shaft. While holding the J-45012 fixture , use the J-34826 socket to tighten the drive pinion nut to 245 N·m (181 lb ft).
12. Remove the J-45012 fixture .
13. Raise the propeller shaft and the front of the RDM until the propeller shaft is installed to the pinion flange.
14. Install the propeller shaft coupler (2) to the differential flange (5).
15. Remove the support.
16. Inspect the propeller shaft to flange nuts (4), bolts (7), and washers (6). Replace if damaged or worn.

Note: If reusing the propeller shaft to flange nuts and bolts, to ensure proper adhesion and fastener retention, the threads must be free of debris prior to the application of threadlocker.

17. Thoroughly clean the threads using denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488) or equivalent to the propeller shaft to the flange bolt. Ensure that there are no gaps in the threadlocker along the length of the filled area of the bolt. Allow the threadlocker to cure approximately 10 minutes before installation.
18. Install the propeller shaft coupler-to-differential flange washers (4) to the propeller shaft coupler-to-differential flange bolts (3).
19. Install the propeller shaft coupler-to-differential flange bolts and washers to the differential flange and propeller shaft coupler.
20. Install the propeller shaft coupler-to-differential flange nuts. Tighten the propeller shaft coupler-to-differential flange bolts to 85 N·m (63 lb ft).
21. Install the bolt from the differential case bracket assembly to body.
22. Remove the RDM support.
23. Install the floor panel tunnel rear panel. Refer to Floor Panel Tunnel Panel Replacement - Rear.
24. Inspect the fluid level. Refer to Rear Axle Lubricant Level Inspection.
25. Lower the vehicle.