8.6 Inch Axle
Drive Pinion Flange/Yoke and/or Oil Seal Replacement (8.6 Inch Axle)Tools Required
^ J8614-01 Flange and Pulley Holding Tool
^ J38694 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. 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.
2. Remove the tire and wheel assemblies.
3. Remove the rear brake calipers.
4. Reference mark the rear propeller shaft (3) to the rear axle pinion yoke (4).
5. 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.
6. 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 oil seal
^ The differential case bearings
^ The axle bearings
^ The axle seals
7. Scribe an alignment line between the pinion shaft and the pinion yoke.
8. Install the J8614-01 as shown.
9. Remove the pinion nut while holding the J8614-01.
Discard the pinion nut.
10. Remove the washer.
11. Install the J8614-2 (2) and the J8614-3 (3) into the J8614-01 (1) as shown.
12. Remove the pinion yoke by turning the J8614-3 (3) clockwise while holding the J8614-01 (1).
Use a container in order to retrieve the lubricant.
13. Remove the pinion oil seal using a suitable seal removal tool.
Installation Procedure
1. Install a new pinion oil seal using the J38694.
2. Apply sealant, GM P/N 12346004 (Canadian P/N 10953480) or equivalent, to the splines of the pinion yoke.
Notice: Refer to Pinion Flange/Yoke Installation Notice in Service Precautions.
3. Install the pinion yoke.
Align the marks made during removal.
4. Install the washer and a new pinion nut.
If the new pinion nut cannot be installed, perform the following steps in order to seat the pinion yoke onto the pinion so that the washer and new pinion nut can be installed:
4.1. Remove the pinion nut washer.
4.2. Install the old pinion nut.
4.3. Tighten the nut until a few of the shaft threads show through the nut so that the washer and new pinion nut can be installed.
4.4. Remove the old pinion nut.
4.5. Install the pinion nut washer
4.6. Install the new pinion nut.
5. Install the J8614-01 onto the pinion yoke as shown.
Notice: Refer to Fastener Notice in Service Precautions.
Important: If the rotating torque is exceeded, the pinion will have to be removed and a new collapsible spacer installed.
6. Tighten the pinion nut while holding the J8614-01.
Tighten the nut until the pinion end play is just taken up. Rotate the pinion while tightening the nut to seat the bearings.
7. 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 (35 inch lbs.) 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 (3) to the pinion yoke (4). Align the reference marks made during removal.
10. Install the propeller shaft yoke retaining clamps and the bolts.
Tighten the propeller shaft yoke retaining clamp bolts to 25 Nm (18 ft. lbs.).
11. Install the brake calipers.
12. Install the tire and wheel assemblies.
13. Inspect and add axle lubricant to the axle housing, if necessary.
14. Lower the vehicle.