GM Service Manual Online
For 1990-2009 cars only

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

Tools Required

    • J 8614-01 Flange and Pulley Holding Tool
    • J 45710 Pinion Bearing Oil Seal Installer

Removal Procedure

    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. Object Number: 788905  Size: SH
  4. Place an alignment mark between the pinion and the pinion yoke.

  5. Object Number: 661080  Size: SH
  6. Install the J 8614-01 as shown.
  7. Remove the pinion nut while holding the J 8614-01 .

  8. Object Number: 815616  Size: SH
  9. Remove the washer.

  10. Object Number: 661074  Size: SH
  11. Install the J 8614-2 (2) and the J 8614-3 (3) into the J 8614-01 (1) as shown.
  12. Remove the pinion yoke by turning the J 8614-3 (3) clockwise while holding the J 8614-01 (1).
  13. Use a container in order to retrieve the lubricant.

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

Installation Procedure

  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. Object Number: 815622  Size: SH
  3. Install the new seal using the J 45710 .

  4. Object Number: 815618  Size: SH
  5. Install the pinion yoke.
  6. Notice: Refer to Pinion Flange/Yoke Installation Notice in the Preface section.

  7. 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.

  8. Object Number: 815616  Size: SH
  9. Install the washer.

  10. Object Number: 815614  Size: SH
  11. Install the new pinion nut

  12. Object Number: 661080  Size: SH
  13. Install the J 8614-01 onto the pinion yoke as shown.
  14. Notice: Refer to Fastener Notice in the Preface section.

  15. Tighten the pinion nut while holding the J 8614-01 .
  16. Tighten
    Tighten the pinion nut to 370 N·m (273 lb ft).

  17. Install the propeller shaft to the rear axle pinion yoke. Refer to One-Piece Propeller Shaft Replacement in Propeller Shaft.
  18. Inspect and add axle lubricant to the axle housing, if necessary. Refer to Lubricant Level Check .
  19. Lower the vehicle.

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

Tools Required

    • J 8614-01 Flange/Pulley Holding Tool
    • J 22388 Rear Axle Pinion Oil Seal Installer (8.6 inch, 9.5 inch axle)
    • J 44414 Rear Axle Pinion Oil Seal Installer (10.5 inch, 11.5 inch axle)

Removal Procedure

    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. Object Number: 361391  Size: SH
  7. Reference mark the rear propeller shaft (3) to the rear axle pinion yoke (4).
  8. Disconnect the propeller shaft from the axle.
  9. Wrap the bearing caps with tape in order to prevent the loss of bearing rollers.

    Support the propeller shaft as necessary.


    Object Number: 661077  Size: SH
  10. 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:
  11. • 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)

    Object Number: 788905  Size: SH
  12. Place an alignment mark between the pinion and the pinion yoke.

  13. Object Number: 661080  Size: SH
  14. Install the J 8614-01 as shown.
  15. Remove the pinion nut while holding the J 8614-01 .
  16. Remove the washer.

  17. Object Number: 661074  Size: SH
  18. Install the J 8614-2 (2) and the J 8614-3 (3) into the J 8614-01 (1) as shown.
  19. Remove the pinion yoke by turning the J 8614-3 (3) clockwise while holding the J 8614-01  (1).
  20. Use a container in order to retrieve the lubricant.

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

Installation Procedure


    Object Number: 651744  Size: SH
  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 (Canadian P/N 10953480) or equivalent to the splines of the pinion yoke.
  3. Install the pinion yoke.
  4. Align the marks made during removal.

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

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

  7. Object Number: 661080  Size: SH
  8. Install the J 8614-01 onto the pinion yoke as shown.
  9. 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.

  10. Tighten the pinion nut while holding the J 8614-01 .
  11. Tighten
    Tighten the nut until the pinion end play is just taken up. Rotate the pinion while tightening the nut to seat the bearings.


    Object Number: 661077  Size: SH
  12. Measure the rotating torque of the pinion. Compare this measurement with the rotating torque recorded during removal.
  13. 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.

  14. 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.

  15. Object Number: 361391  Size: SH
  16. Install the propeller shaft (3) to the pinion yoke (4).
  17. Align the reference marks made during removal.

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

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