Rear Drive Axle

Drive Pinion Flange/Yoke and/or Oil Seal Replacement


Special Tools
* J 42851 Seal Installer
* J 45012 Holding Fixture
* J 45019 Flange and Pinion Cage Remover
* J 34826 Hub Nut Socket (36 mm)



Removal Procedure

1. Raise and support vehicle. Refer to Lifting and Jacking the Vehicle (Service and Repair) .
2. Remove the exhaust system. Refer to Exhaust System Replacement (With LY7 and LLT) (Exhaust System Replacement (With LY7 and LLT))Exhaust System Replacement (With LP1) (Exhaust System Replacement (With LP1)) .
3. Remove the propeller shaft. Refer to Rear Propeller Shaft Replacement (RWD) (Rear Propeller Shaft Replacement)Rear Propeller Shaft Replacement (AWD) (Rear Propeller Shaft Replacement) .




4. Use the J 45012 to hold the pinion flange.
5. Using the J 34826 , remove the drive pinion nut.




6. Using the J 45019 , remove the flange.
7. Using a flat-bladed tool, remove the drive pinion seal. Take care not to damage any sealing surfaces.



Installation Procedure


Important: Ensure the pinion bore is free of dirt debris.


1. Apply a small amount of synthetic gear oil GM P/N 12378514 (Canadian P/N 88901045) or equivalent to the drive pinion flange sealing surface of the drive pinion seal.




2. Using the J 42851 (1), install the pinion seal (2) to the differential housing (3).




3. Install the J 45012 on the drive pinion shaft.
4. Install the pinion flange on the drive pinion shaft.

Important: The pinion shaft threads and the pinion flange nut must be free of residue and debris prior to the application of the threadlocker.


5. Thoroughly clean the residue from the pinion shaft threads and the pinion flange nut by using denatured alcohol or equivalent and allow to dry.
6. 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.
7. Allow the threadlocker to cure approximately 10 minutes before installation.
8. Use the J 45012 to hold the pinion flange.

Notice: Refer to Fastener Notice (Fastener Notice) .

9. Using the J 34826 , tighten the drive pinion nut.

Tighten the pinion flange nut to 285 N.m (210 lb ft).

10. Install the propeller shaft. Refer to Rear Propeller Shaft Replacement (RWD) (Rear Propeller Shaft Replacement)Rear Propeller Shaft Replacement (AWD) (Rear Propeller Shaft Replacement) .
11. Inspect the fluid level. Refer to Rear Axle Lubricant Level Inspection (Rear Drive Axle) .
12. Install the exhaust system. Refer to Exhaust System Replacement (With LY7 and LLT) (Exhaust System Replacement (With LY7 and LLT))Exhaust System Replacement (With LP1) (Exhaust System Replacement (With LP1)) .
13. Lower the vehicle.