Drive Pinion Flange/Yoke and/or Oil Seal Replacement
Drive Pinion Flange/Yoke and/or Oil Seal Replacement
Tools Required
- J 8614-01 Flange/Pulley Holding Tool.
- J 22388 Pinion Oil Seal Installer - Rear.
- J 33782 Pinion Oil Seal Installer.
- J 38694 Extension Housing Oil Pump/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. Assemble all the components in the exact places in which you removed the parts. Follow any specifications, torque values, and measurements obtained prior to disassembly.
1. Raise the vehicle.
2. Remove the tire and wheel assemblies.
3. Remove the rear brake calipers, if equipped.
4. Remove the brake rotors, if equipped.
5. Remove the brake drums, if equipped.
6. Disconnect the propeller shaft from the drive pinion yoke.
- Position and secure the propeller shaft away from the rear axle.
7. Measure the amount of torque required to rotate the pinion using an inch-pound torque wrench. This will give the combined preload for the following components:
- The pinion bearings.
- The pinion seal.
- The carrier bearings.
- The axle bearings.
- The axle seals.
8. Record the measurement.
9. Draw an alignment mark between the pinion stem and the pinion flange/yoke.
10. Install the J 8614-01 as shown.
11. Remove the pinion nut while holding the J 8614-01.
12. Remove the washer.
13. Install the J 8614-2 (2) and the J 8614-3 (3) into the J 8614-01 (1) as shown.
14. 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.
Important: Do not damage the axle housing sealing surface.
15. Remove the pinion oil seal using a suitable seal removal tool.
Installation Procedure
1. Install the new pinion oil seal using one of the following:
- For vehicles with a 7.6 inch axle, 2-Door Utilities and 4WD Pickups w/ RPO M50 and w/o RPO ZR2, use the J 33782.
- For 2-Door Utilities and 4WD Pickups w/ RPO ZR2, use the J 22388 (1st design 8.6 inch axle) or the J 38694 (2nd design 8.6 inch axle).
2. Apply sealant, GM P/N 12346004 (Canadian P/N 10953480) or equivalent, to the splines of the pinion flange/yoke.
Important: Install the pinion gear flange/yoke to the pinion gear shaft in the same position as marked during removal in order to maintain correct driveline balance.
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 flange/yoke onto the pinion shaft by tapping it with a soft-faced hammer until a few pinion shaft threads show through the flange/yoke.
5. Install the washer and a new pinion nut.
6. Install the J 8614-01 onto the pinion flange/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 the nut until the pinion end play is removed. 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 the nut in small increments, as needed, until the rotating torque is 0.40-0.57 Nm (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. Check the rotating torque and adjust if necessary.
10. Install the propeller shaft to the drive pinion flange/yoke.
11. Install the brake drums, if equipped.
12. Install the brake rotors, if equipped.
13. Install the brake calipers, if equipped.
14. Install the tire and wheel assemblies.
15. Inspect and add axle lubricant to the axle housing, if necessary.
16. Lower the vehicle.