Drive Pinion Flange/Yoke and/or Oil Seal Replacement All Except 9.75 Inch Axle

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 and support the vehicle. Refer to Lifting and Jacking the Vehicle.
2. Remove the tire and wheel assemblies (8.6 inch, 9.5 inch axles). Refer to Tire and Wheel Removal and Installation.
3. Remove the rear brake calipers (8.6 inch, 9.5 inch axles). Refer to Rear Brake Caliper Replacement.
4. Remove the brake rotors (8.6 inch, 9.5 inch axles). Refer to Rear Brake Rotor Replacement.
5. Remove the axle shafts (10.5 inch, 11.5 inch axle). Refer to Rear Axle Shaft and/or Gasket Replacement.
6. Remove the propeller shaft from the vehicle.

•	For vehicles equipped with the one piece propeller shaft, refer to One-Piece Propeller Shaft Replacement.

•	For vehicles equipped with the two piece propeller shaft, refer to Two-Piece Propeller Shaft Replacement.




7. Using an inch-pound torque wrench, and record measure the amount of torque required to rotate the pinion. 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)




8. Place a reference mark on the pinion and the pinion yoke.




Important: DO NOT re-use the pinion nut. Replace with new only.

9. Using the J 8614-01 , remove the pinion nut and washer. Discard the nut.



10. Using the J 8614-2 (2), J 8614-3 (3) and the J 8614-01  (1), remove the pinion yoke.
11. Using a suitable tool, remove the pinion oil seal.

1. Using the J 22388 (8.6 inch, 9.5 inch axles) or the J 44414 (10.5 inch, 11.5 inch axle), install the pinion oil seal.
2. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) to the splines of the pinion yoke.
3. Aligning the reference marks, install the pinion yoke.

Notice: Refer to Pinion Flange/Yoke Installation Notice in the Preface section.

4. Using a soft faced hammer, tap the pinion yoke on the drive pinion until a few threads of the drive pinion are showing.
5. Install the washer and a NEW pinion nut.

Notice: Refer to Fastener Notice in the Preface section.





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

6. Using the J 8614-01 , tighten the pinion nut.

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




7. Using an inch pound torque wrench, measure the rotating torque of the pinion and compare this measurement 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.

8. 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.
9. Install the propeller shaft.

•	For vehicles equipped with the one piece propeller shaft, refer to One-Piece Propeller Shaft Replacement.

•	For vehicles equipped with the two piece propeller shaft, refer to Two-Piece Propeller Shaft Replacement.

10. Install the axle shafts (10.5 inch, 11.5 inch axle). Refer to Rear Axle Shaft and/or Gasket Replacement.
11. Install the brake rotors (8.6 inch, 9.5 inch axles). Refer to Rear Brake Rotor Replacement.
12. Install the brake calipers (8.6 inch, 9.5 inch axles). Refer to Rear Brake Caliper Replacement.
13. Install the tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation.
14. Inspect and add axle lubricant to the axle housing, if necessary. Refer to Rear Axle Lubricant Level Inspection.
15. Remove the support and lower the vehicle.

Drive Pinion Flange/Yoke and/or Oil Seal Replacement 9.75 Inch Axle

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. Disconnect the propeller shaft from the rear axle pinion yoke. Refer to One-Piece Propeller Shaft Replacement in Propeller Shaft.



3. Place an alignment mark between the pinion and the pinion yoke.



4. Install the J 8614-01 as shown.
5. Remove the pinion nut while holding the J 8614-01 .



6. Remove the washer.



7. Install the J 8614-2 (2) and the J 8614-3 (3) into the J 8614-01 (1) as shown.
8. 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.

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

1. Apply a light coat of axle lubricant, GM P/N 12378557 or equivalent meeting GM Specification 9986207, to the lip of the pinion seal.



2. Install the new seal using the J 45710 .



3. Install the pinion yoke.

Notice: Refer to Pinion Flange/Yoke Installation Notice in the Preface section.

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.



6. Install the new pinion nut



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

Notice: Refer to Fastener Notice in the Preface section.

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

Tighten
Tighten the pinion nut to 370 N·m (273 lb ft).

9. Install the propeller shaft to the rear axle pinion yoke. Refer to One-Piece Propeller Shaft Replacement in Propeller Shaft.
10. Inspect and add axle lubricant to the axle housing, if necessary. Refer to Rear Axle Lubricant Level Inspection .
11. Lower the vehicle.