Drive Pinion and Ring Gear Replacement 8.6/9.5 Inch Axle LD

Tools Required

1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle .
2. Remove the tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation .
3. Remove the brake calipers. Refer to Rear Brake Caliper Replacement .
4. Remove the brake rotors. Refer to Rear Brake Rotor Replacement .
5. Remove the axle shafts. Refer to Rear Axle Shaft Replacement .
6. Remove the differential assembly. Refer to Differential Replacement .
7. Remove the drive pinion yoke and the oil seal. Refer to Drive Pinion Flange/Yoke and/or Oil Seal Replacement .



8. Install the J 22536 as shown.

Ensure that the J 22536 is firmly seated on the pinion.

9. Drive the pinion out using the J 22536 and a hammer.

Strike the J 22536 slowly. Do not let the pinion fall out of the rear axle housing.




10. Remove the collapsible spacer from the pinion. Discard the spacer.
11. Remove the pinion bearings and the cups. Refer to Drive Pinion Bearings Replacement .
12. Remove the left-hand threaded ring gear bolts. Discard the bolts.
13. Remove the ring gear from the differential. Drive the gear off with a brass drift if necessary.

Important: The mating surface of the ring gear and the differential case must be clean and free of burrs before installing the ring gear.

1. Install the ring gear to the differential case.
2. Install the new ring gear bolts.

Hand start each bolt to ensure that the ring gear is properly installed to the differential case.

Notice: Refer to Fastener Notice in the Preface section.

3. Tighten the new ring gear bolts alternately and in stages, gradually pulling the ring gear onto the differential case.

Tighten
Tighten the ring gear bolts in sequence to 120 N·m (89 lb ft).

4. Install the drive pinion bearing cups. Refer to Drive Pinion Bearings Replacement .
5. Determine the selective shim thickness for the pinion gear. Refer to Pinion Depth Adjustment .
6. Install the selective shim onto the pinion.
7. Install the inner pinion bearing onto the pinion. Refer to Drive Pinion Bearings Replacement .
8. Install a new collapsible spacer.
9. Lubricate the pinion bearings with axle lubricant. Refer to Fluid and Lubricant Recommendations .
10. Install the pinion to the axle housing.
11. Install the outer pinion bearing.



12. Install a new pinion oil seal using the J 38694 .
13. Apply sealant, GM P/N 12346004 (Canadian P/N 10953480) or equivalent, to the splines of the pinion yoke.



14. Install the pinion yoke.

Align the marks made during removal.

15. Seat the pinion yoke onto the pinion shaft by tapping it with a soft-faced hammer until a few pinion shaft threads show through the yoke.
16. Install the washer and a new pinion nut.



17. Install the J 8614-01 onto the pinion yoke as shown.

Important: If the rotating torque is exceeded, the pinion will have to be removed and a new collapsible spacer installed.

18. Tighten the pinion nut while holding the J 8614-01 .

Tighten
Tighten the pinion nut until the pinion end play is just taken up. Rotate the pinion while tightening the nut to seat the bearings.




19. Measure the rotating torque of the pinion using an inch-pound torque wrench.

Specification
The rotating torque of the pinion should be 1.0-2.3 N·m (10-20 lb in) for used bearings or 1.7-3.4 N·m (15-30 lb in) for new bearings.

20. If the rotating torque measurement is below 1.0 N·m (10 lb in) for used bearings, or 1.7 N·m (15 lb in) for new bearings, continue to tighten the pinion nut.

Tighten
Tighten the pinion nut, in small increments, as needed, until the torque required in order to rotate the pinion is 1.0-2.3 N·m (10-20 lb in) for used bearings or 1.7-3.4 N·m (15-30 lb in) for new bearings.

21. Once the specified torque is obtained, rotate the pinion several times to ensure the bearings have seated.

Recheck the rotating torque and adjust if necessary.

22. Install the differential. Refer to Differential Replacement .
23. Perform a gear tooth contact pattern check on the pinion and the ring gear. Refer to Gear Tooth Contact Pattern Inspection .
24. Install the axle shafts. Refer to Rear Axle Shaft Replacement .
25. Install the brake rotors. Refer to Rear Brake Rotor Replacement .
26. Install the brake calipers. Refer to Rear Brake Caliper Replacement .
27. Install the tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation .
28. Fill the axle with axle lubricant. Use the proper fluid. Refer to Rear Axle Lubricant Replacement .
29. Lower the vehicle.