Tools Required

Important: Observe and mark the positions of all the driveline components, relative to the propeller shaft and the axles, prior to disassembly. These components include the propeller shafts, drive axles, pinion flanges, output shafts, etc. Reassemble all the components in the exact places in which you removed the parts. Follow any specifications, torque values, and any measurements made prior to disassembly.

1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Remove the tire and wheel assemblies (8.6 inch, 9.5 inch axles). Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
3. Remove the rear brake calipers (8.6 inch, 9.5 inch axles). Refer to Rear Brake Caliper Replacement in Disc Brakes.
4. Remove the brake rotors (8.6 inch, 9.5 inch axles). Refer to Rear Brake Rotor Replacement in Disc Brakes.
5. Remove the axle shafts (10.5 inch, 11.5 inch axle). Refer to Rear Axle Shaft and/or Gasket Replacement .



6. Reference mark the rear propeller shaft (3) to the rear axle pinion yoke (4).
7. Disconnect the propeller shaft from the axle.

Wrap the bearing caps with tape in order to prevent the loss of bearing rollers.

Support the propeller shaft as necessary.




8. Measure the amount of torque required to rotate the pinion. Use an inch-pound torque wrench. Record this measurement for reassembly. This will give the combined preload for the following components:

•	The pinion bearings

•	The pinion pilot bearing (10.5 inch axle)

•	The pinion oil seal

•	The differential case bearings

•	The axle bearings (8.6 inch, 9.5 inch axles)

•	The axle seals (8.6 inch, 9.5 inch axles)

9. Draw 2 arrows pointing at each other, one on the pinion stem, the other on the pinion yoke.
10. Record the number of exposed threads on the pinion stem for reference.



11. Install the J 8614-01 as shown.
12. Remove the pinion nut while holding the J 8614-01 .
13. Remove the washer.



14. Install the J 8614-2 (2) and the J 8614-3 (3) into the J 8614-01 (1) as shown.
15. Remove the pinion yoke by turning the J 8614-3 (3) clockwise while holding the J 8614-01 (1).

Use a container in order to retrieve the lubricant.

16. Remove the pinion oil seal. Use a suitable seal removal tool. Do not damage the housing.

1. Install a new pinion oil seal using the J 22388 (8.6 inch, 9.5 inch axles) or the J 44414 (10.5 inch, 11.5 inch axle).
2. Apply sealant (GM P/N 12346004 or equivalent) to the splines of the pinion yoke.
3. Install the pinion yoke.

Align the marks made during removal.

Notice: Do not hammer the pinion flange/yoke onto the pinion shaft. Pinion components may be damaged if the pinion flange/yoke is hammered onto the pinion shaft.

4. 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.
5. Install the washer and a new pinion nut.



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

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

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

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

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




8. Measure the rotating torque of the pinion. Compare this measurement with the rotating torque recorded during removal.

Tighten
Tighten the nut in small increments, as needed, until the rotating torque is 0.40-0.57 N·m (3- 5 lb in) greater than the rotating torque recorded during removal.

9. 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.



10. Install the propeller shaft (3) to the pinion yoke (4).

Align the reference marks made during removal.

11. Install the propeller shaft yoke retaining clamps and the bolts.

Tighten
Tighten the propeller shaft yoke retaining clamp bolts to 25 N·m (18 lb ft).

12. Install the axle shafts (10.5 inch, 11.5 inch axle). Refer to Rear Axle Shaft and/or Gasket Replacement .
13. Install the brake rotors (8.6 inch, 9.5 inch axles). Refer to Rear Brake Rotor Replacement in Disc Brakes.
14. Install the brake calipers (8.6 inch, 9.5 inch axles). Refer to Rear Brake Caliper Replacement in Disc Brakes.
15. Install the tire and the wheel. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
16. Inspect and add axle lubricant to the axle housing, if necessary. Refer to Lubricant Level Check .
17. Lower the vehicle.