Seals and Gaskets: Service and Repair

Differential Drive Pinion Flange/Yoke, Seal, and Dust Deflector Replacement - Front

^ Tools Required
^ J 8614-01 Flange and Pulley Holding Tool
^ J 36366 Pinion Oil Seal Installer

Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
2. Remove the tire and wheel assemblies.
3. Remove the brake calipers.
4. Remove the engine protection shield.
5. Reference mark the relationship of the propeller shaft to the front axle pinion yoke.





6. Remove the yoke retainer bolts (6) and the yoke retainers (7) from the front axle pinion yoke (1).

7. Disconnect the propeller shaft (2) from the front axle pinion yoke (1). Wrap the bearing caps with tape in order to prevent the loss of bearing rollers.

Notice: When removing the propeller shaft, do not attempt to remove the shaft by pounding on the yoke ears or using a tool between the yoke and the universal joint. If the propeller shaft is removed by using such means, the injection joints may fracture and lead to premature failure of the joint.

8. Support the propeller shaft and move out of the way as necessary.





9. Measure the torque required in order to rotate the pinion. Use an inch-pound torque wrench. Record the torque value for reassembly. 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





10. Scribe a line (1) on the pinion shaft and the pinion yoke (2).





11. Install the J 8614-01 onto the pinion as shown.
12. Remove the pinion nut while holding the J 8614-01.





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).

15. Remove the oil seal using a suitable seal removal tool.

Important: Carefully pry the seal from the bore. Do not distort or scratch the aluminum case.


Installation Procedure





1. Install the oil seal by doing the following:
1. Position the oil seal in the bore.
2. Install the J 36366 over the oil seal.
3. Strike the J 36366 with a hammer until the seal flange seats on the axle housing surface.

Important: Drive the seal in straight, not at an angle.

2. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the splines of the drive pinion yoke.
3. Install the pinion yoke.Align the reference marks made during removal.

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.

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.

5. Install the washer and a new pinion nut.





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

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

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.

8. Measure the rotating torque of the pinion using an inch-pound torque wrench.Compare the measurement with the rotating torque recorded earlier.
^ Tighten the pinion nut, in small increments, as needed, until the torque required in order to rotate the pinion is 0.40 - 0.57 Nm (3 - 5 inch lbs.) greater than the torque recorded during removal.
9. 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.





10. Install the propeller shaft (5) to the pinion yoke (1).Align the reference marks made during removal.
11. Install the yoke retainers (7) and the yoke retainer bolts (6) to the pinion yoke (1).
^ Tighten the yoke retainer bolts to 25 Nm (18 ft. lbs.).
12. Inspect the axle lubricant level, and add, if necessary.
13. Install the engine protection shield.
14. Install the brake calipers.
15. Install the tire and wheel assemblies.
16. Lower the vehicle.