GM Service Manual Online
For 1990-2009 cars only

Drive Pinion Flange/Yoke and/or Oil Seal Replacement 8.6, 9.5, 10.5 Inch Axle

Tools Required

    • J 8614-01 Flange/Pulley Holding Tool
    • J 22388 Pinion Oil Seal Installer-Rear
    • J 44414 Pinion 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. 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 drums (8.6 inch, 9.5 inch axles). Refer to Brake Drum Replacement in Drum Brakes.
  4. Remove the axle shafts (10.5 inch axle). Refer to Rear Axle Shaft and/or Gasket Replacement .
  5. Disconnect the propeller shaft from the rear axle. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement in Propeller Shaft.

  6. Object Number: 661077  Size: SH
  7. 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:
  8. • The pinion bearings
    • The pinion oil seal
    • The differential case bearings
    • The axle bearings, 8.6 and 9.5 inch axles
    • The axle seals, 8.6 and 9.5 inch axles

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

  10. Object Number: 661080  Size: SH
  11. Install the J 8614-01 as shown.
  12. Remove the pinion nut while holding the J 8614-01 .
  13. Remove the washer.

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

  18. 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 seal using the J 22388 (8.6 inch, 9.5 inch axle) or the J 44414 (10.5 inch axle).
  2. Apply sealant (GM P/N 12346004 or equivalent) to the splines of the pinion yoke.

  3. Object Number: 788905  Size: SH
  4. Install the pinion yoke.
  5. Align the marks made during removal.

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

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

  8. Object Number: 661080  Size: SH
  9. Install the J 8614-01 onto the pinion yoke as shown.
  10. 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.

  11. Tighten the pinion nut while holding the J 8614-01 .
  12. 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
  13. Measure the rotating torque of the pinion. Compare this measurement with the rotating torque recorded during removal.
  14. 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.

  15. 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.
  16. Install the propeller shaft to the rear axle pinion yoke or to the yoke flange. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement in Propeller Shaft.
  17. Install the axle shafts (10.5 inch axle). Refer to Rear Axle Shaft and/or Gasket Replacement .
  18. Install the brake drums (8.6 inch, 9.5 inch axles). Refer to Brake Drum Replacement in Drum Brakes.
  19. Install the tire and the wheel (8.6 inch, 9.5 inch axles). Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  20. Inspect and add axle lubricant to the axle housing, if necessary. Refer to Lubricant Level Check .
  21. Lower the vehicle.

Drive Pinion Flange/Yoke and/or Oil Seal Replacement 11 Inch Axle

Tools Required

    • J 8614-01 Flange and Pulley Holding Tool
    • J 41696 Pinion 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 Two-Piece Propeller Shaft Replacement or Three-Piece Propeller Shaft Replacement in Propeller Shaft.

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

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

  11. 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 12346140 or equivalent) to the lip of the pinion seal.

  2. Object Number: 651744  Size: SH
  3. Install the new seal using the J 41696 .
  4. Install the pinion yoke.
  5. 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.

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

  8. Object Number: 661080  Size: SH
  9. Install the J 8614-01 onto the pinion yoke as shown.
  10. 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.

  11. Tighten the pinion nut while holding the J 8614-01 .
  12. Tighten
    Tighten the pinion nut to 637 N·m (470 lb ft).

  13. Install the propeller shaft to the rear axle pinion yoke. Refer to Two-Piece Propeller Shaft Replacement or Three-Piece Propeller Shaft Replacement in Propeller Shaft.
  14. Inspect and add axle lubricant to the axle housing, if necessary. Refer to Lubricant Level Check .
  15. Lower the vehicle.