8.6 Inch Axle

Rear Axle - Assemble (8.6 Inch Axle)
^ Tools Required
- J 8092 Driver Handle
- J 8608 Rear Pinion Bearing Race Installer
- J 8611-01 Rear Pinion Bearing Race Installer
- J 8614-01 Flange/Pulley Holding Tool
- J 21128 Axle Shaft Seal Installer
- J 22388 Pinion Oil Seal Installer - Rear
- J 23690 Axle Shaft Bearing Installer
- J 24433 Pinion Cone and Side Bearing Installer





1. Install the outer pinion bearing cup using the J8611-01 (2) and the J8092 (1).





2. Install the inner pinion bearing cup using the J 8608 (1) and the J 8092 (2).
3. Determine the selective shim thickness for the pinion.





4. Install the selective shim between the inner pinion bearing and the shoulder on the gear.
5. Install the inner pinion bearing using the J24433. Press the bearing on until the cone seats on the pinion shim.
6. Install a new collapsible spacer.
7. Lubricate the pinion bearings with axle lubricant. Use the proper fluid.
8. Install the pinion into the axle housing.
9. Install the outer pinion bearing onto the pinion.





10. Install a new seal using the J 22388.
11. Apply sealant, GM P/N 12346004 or equivalent, to the splines of the pinion yoke.
12. Install the pinion yoke.
Align the marks make 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.

13. 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.
14. Install the washer and a new pinion nut.





15. 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.

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





17. Lubricate the differential side bearings with axle lubricant. Use the proper fluid.
18. Place the differential case, with the bearing cups installed, into the axle housing.





19. Install the bearing caps and the bolts.
Do not torque the bearing cap bolts at this time.
20. Adjust the differential side bearing preload.





21. 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 inch lbs.) greater than the rotating torque recorded during removal.
22. 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.
23. Adjust the backlash.
24. Perform a gear tooth contact pattern check.
25. Tighten the bearing cap bolts.
^ Tighten the bearing cap bolts to 75 Nm (55 lb ft).





26. Install the axle shaft bearing using the J23690 (1) and the J8092 (2).
27. Drive the axle shaft bearing into the axle housing until the tool bottoms against the tube.





28. Install the axle shaft seal using the J 21128.
29. Drive the tool into the bore until the axle shaft seal bottoms flush with the tube.





Important: Carefully insert the axle shaft in order to not damage the seal.

30. Install the axle shaft (1) into the housing (5).
31. Slide the axle shaft (1) into place allowing the splines to engage the differential side gear.
32. On axles without a locking differential, place the lock (4) on the button end of the axle shaft (1).
33. On axles with a locking differential, keep the pinion shaft partially withdrawn.





34. On axles with a locking differential, place the lock (1) on the axle shaft (3) so that the ends are flush with the thrust block (2).
35. Pull the shaft flange outward in order to seat the lock in the differential gear.





36. Align the hole in the pinion shaft with the bolt hole in the differential case.
37. Install the new pinion shaft locking bolt.
^ Tighten the pinion shaft locking bolt to 36 Nm (27 lb ft).





38. Install the rear axle housing cover (2) and a new gasket.

Important: Do not reuse the rear axle housing cover bolts.

39. Install the new rear axle housing cover bolts (1).
^ Tighten the rear housing cover bolts in a crosswise pattern to 40 Nm (30 lb ft).





40. Install the drain plug.
^ Tighten the drain plug to 33 Nm (24 lb ft).
41. Fill the axle using the proper fluid.





42. Install the fill plug.
^ Tighten the fill plug to 33 Nm (24 lb ft).