Pinion Flange: Service and Repair

Drive Pinion Flange Yoke and/or Oil Seal Replacement

^ Tools Required
- J 45019 Flange and Pinion Cage Remover
- J 45059 Angle Meter
- J 42094-A Remover/installer Kit
- DT-46853 Pinion Oil Seal Installer

Removal Procedure
1. Raise and support the vehicle.
2. Remove the left and right mufflers.

3. Remove the propeller shaft.
4. Place a drain pan under the pinion flange.

Important: The rear axle lubricant must be completely drained to ensure the proper friction modifier fill specification.

5. Remove the rear axle housing drain plug from the axle housing.
6. Remove the rear axle housing fill plug from the axle housing.





7. Center punch alignment marks (1) on the pinion flange, the pinion flange nut (2), and the pinion shaft end.





8. Using an inch pound torque wrench, check and record the rotational torque on the pinion shaft. Torque should be between 2 and 4 inch lbs.).





9. Install pinion flange holding tool CH-46865-1 on the pinion flange.
10. Remove the pinion flange nut.





11. Using J 45019 remove the pinion flange.





12. Using a seal puller, remove the pinion seal.

Installation Procedure





1. Inspect the pinion shaft seal surface for nicks and burrs. Minor nicks and burrs can be removed with crocus cloth. If damaged, replace the pinion flange.
2. Clean the threads on the pinion shaft and pinion nut.
3. Coat the pinion shaft splines with recommended gear oil.
4. Lubricate the seal with the recommended gear oil.
5. Using DT-46853 pinion seal installer, install the new pinion shaft seal until the seal is flush with the differential housing.
6. Install the pinion flange on to the pinion shaft aligning the punch marks.





7. Install pinion flange holding tool CH-46865-1 (1) on the pinion flange.





8. Apply thread locking compound onto the threads of the pinion shaft.

Important: Do not overtighten the pinion nut. If the nut is overtightened the preload will be exceeded and the differential will have to be changed.

Notice: Refer to Fastener Notice in Service Precautions.

9. Tighten the pinion nut until the three punch marks are aligned.
^ Using J 45059, tighten the nut to a position no more than 5 degrees past the punch marks.





10. Using a inch pound torque wrench, recheck the rotational torque on the pinion shaft. The torque should be between 2 and 4 inch lbs.).
11. Install the drain plug.
^ Tighten the drain plug to 27 Nm (20 ft. lbs.).
12. Refill the rear axle housing with 1.0 liter (1.0 qt) of Synthetic Gear Oil 75W-140 GM P/N 890211809.
13. Using a graduated measuring cup, add 25 ml (1.0 oz) of Limited Slip Differential Friction Modifier GM P/N 89021958 to the rear axle housing.
14. Fill the rear axle housing with the remaining 0.575 liter (0.644 qt) of Synthetic Gear Oil 75W-140 GM P/N 890211809.
The oil level should be even with the bottom of the rear axle housing filler plug hole.
15. Install the rear axle housing oil level fill plug with a new gasket and the lubricant tag into the rear axle housing.
^ Tighten the fill plug to 27 Nm (20 ft. lbs.).
16. Remove the drain pan.
17. Install the propeller shaft.
18. Install the left and right mufflers.
19. Lower the vehicle.