Pinion Depth Adjustment 8.6 Inch Axle

Note: The differential side bearing bores and the pinion bearing cups must be clean and free of any debris before proceeding with the pinion bearing adjustment.

1. Lubricate the pinion bearings with the proper axle lubricant. Refer to Fluid and Lubricant Recommendations.
2. Install the pinion bearings into the rear axle housing.



3. Install the J 21777-35 (1), the J 21777-43 (2), the J 21777-42 (3), and the J 21777-29 (4) in the rear axle housing.

Note: Rotate the assembly several times in both directions in order to seat the pinion bearings.

4. Using a inch pound torque wrench and holding the J 21777-43, tighten the nut of the J 21777-43 until a rotating torque of 1.7 N·m (15 lb in) is obtained.
5. Check the rotating torque of the assembly. If the torque is less than 1.7 N·m (15 lb in), tighten the nut on the J 21777-43 until a rotating torque of 1.7-2.3 N·m (15-20 lb in) is obtained.



6. Install the J 21777-45 (1, 2) to the J 21777-1 (3) in the rear axle housing.
7. Install the differential bearing caps.

Caution: Refer to Fastener Caution in the Preface section.

8. Install the bearing cap bolts to 75 N·m (55 lb ft)..

Note: In the following service procedure, J 21777-1 must rotate back and forth freely within the discs. If the J 21777-1 does not rotate freely, disassemble the components, inspect for proper seating and/or mis-aligned components and re-assemble.

9. Rotate the J 21777-1 within the J 21777-45.



10. Align the plunger of the J 21777-1 (1) to the gage block setting of the J 21777-29.
11. Loosely clamp the J 8001 indicator on the stem on the J 21777-1.
12. Place the contact pad of the J 8001 indicator on the mounting post of the J 21777-1.
13. With the contact pad of the J 8001 indicator touching the mounting post of the J 21777-1, loosen the lock nut on the J 8001 indicator and push down on the J 8001 indicator until the needle the J 8001 indicator has turned 3/4 of a turn clockwise.
14. Tighten the clamp on the J 8001 indicator finger tight.

Note: The deflection is the point where the needle changes direction.

15. Move the plunger of the J 21777-1 back and forth until the needle of the J 8001 indicator indicates the greatest deflection.



16. At the greatest point of deflection, move the housing of the J 8001 indicator until the needle indicates zero.
17. Move the plunger of the J 21777-1 back and forth again to verify the zero setting. Adjust the housing of the J 8001 indicator as necessary to set the needle to zero.
18. Rotate the plunger of the J 21777-1 away from the J 21777-29 until it no longer touches the J 21777-29.
19. The value indicated on the J 8001 indicator is the thickness of the shim needed in order to set the depth of the pinion.

Note: Measure the shim with a micrometer in order to verify that the thickness is correct.

20. Select the shim that indicates the proper thickness.
21. Remove the pinion depth setting tools.
22. Remove the pinion bearings.
23. Install the pinion shim between the pinion gear and the inner pinion bearing. Refer to Drive Pinion Bearings Replacement.

Pinion Depth Adjustment 9.5LD Inch Axle

Note: The differential side bearing bores and pinion bearing cups must be clean and free of any debris before proceeding with the pinion bearing adjustment.

1. Lubricate the pinion bearings with axle lubricant. Use the proper fluid. Refer to Fluid and Lubricant Recommendations.
2. Install the pinion bearings into the rear axle housing.



3. Install the J 21777-8 (1), the J 21777-43 (2), the J 21777-42 (3), and the J 21777-85 (4) in the rear axle housing.
4. Using a inch pound torque wrench and holding the J 21777-43 stationary, slowly tighten the nut of the J 21777-43 until a rotating torque of 1.1-2.2 N·m (10-20 lb in) is obtained.

Note: Rotate the assembly several times in both directions in order to seat the pinion bearings.

5. Using an inch-pound torque wrench, measure the rotating torque of the assembly which should be 1.1-2.3 N·m (10-20 lb in)..
6. If the rotating torque of the assembly is less than 1.1N·m (10 lb in), continue to tighten the nut on the J 21777-43 until a rotating torque of 1.1-2.3  N·m(10-20 lb in) is obtained.




Note: 2 of the J 21777-86 will needed to perform the following procedure.

7. Install the J 21777-86 (1), (2) and the J 21777-1 (3) in the rear axle housing.
8. Install the differential bearing caps.

Caution: Refer to Fastener Caution in the Preface section.

9. Install the differential bearing cap bolts and tighten to 85 N·m (63 lb ft)..

Note: The J 21777-1 must rotate back and forth freely within the discs. If the J 21777-1 does not rotate freely, disassemble the components, inspect for proper seating and/or mis-aligned components and re-assemble.

10. Rotate the J 21777-1 within the J 21777-86.



11. Align the plunger of the J 21777-1 (1) to the J 21777-85 gage and plate  (2).
12. Loosely clamp the J 8001 indicator  (1) on the stem on the J 21777-1.
13. Place the contact pad of the J 8001 indicator on the mounting post of the J 21777-1.
14. With the contact pad of the J 8001 indicator touching the mounting post of the J 21777-1, loosen the lock nut on the J 8001 indicator and push down on the J 8001 indicator until the needle the J 8001 indicator has turned 3/4 of a turn clockwise.
15. Tighten the clamp on the J 8001 indicator finger tight.

Note: The greatest amount of deflection is the point where the needle changes direction.

16. Move the plunger of the J 21777-1 back and forth until the needle of the J 8001 indicator indicates the greatest amount of deflection.



17. At the greatest point of deflection, move the housing of the J 8001 indicator until the needle indicates ZERO.
18. Move the plunger of the J 21777-1 back and forth again to verify the ZERO setting. Adjust the housing of the J 8001 indicator as necessary to set the needle to ZERO.
19. Rotate the plunger of the J 21777-1 away from the J 21777-85 until it no longer touches the J 21777-85.
20. The value indicated on the J 8001 indicator is the thickness of the shim needed in order to set the depth of the pinion.

Note: Measure the shim with a micrometer in order to verify that the thickness is correct.

21. Select the shim that indicates the proper thickness.
22. Remove the pinion depth setting tools.
23. Remove the pinion bearings.
24. Install the pinion shim between the pinion gear and the inner pinion bearing. Refer to Drive Pinion Bearings Replacement.

Pinion Depth Adjustment 10.5 Inch Axle

1. Install the differential, if necessary. Refer to Differential Replacement.

Note: Measure and record the thickness of the pinion gear bearing retainer shim before any service procedures are performed to the pinion gear bearing retainer assembly.

2. Install the original shim to the pinion bearing retainer. If the original shim is not available, install a 0.41 mm (0.016 in) shim to build pinion depth.

Note: Do not apply sealant to the pinion gear bearing retainer at this time.

3. Install the pinion gear bearing retainer.

Caution: Refer to Fastener Caution in the Preface section.

4. Install the pinion gear bearing retainer bolts and tighten to 88 N·m (65 lb ft)..
5. Adjust the backlash. Refer to Backlash Adjustment.
6. Perform a gear tooth pattern check on the pinion and the ring gear. Refer to Gear Tooth Contact Pattern Inspection.
7. If the gear tooth contact pattern indicates a high or a low flank contact pattern, adjust the pinion depth by doing the following:

7.1.	Remove the pinion gear bearing retainer bolts.

7.2.	Remove the pinion gear bearing retainer.

7.3.	Remove the shim.

•	If the gear tooth contact pattern shows a high flank contact pattern, install a shim one size larger.

•	If the gear tooth contact pattern shows a low flank contact pattern, install a shim one size smaller.

7.4.	Install the new shim to the pinion gear bearing retainer.

7.5.	Install pinion gear bearing retainer.

7.6.	Install pinion gear bearing retainer bolts and tighten to 88 N·m (65 lb ft)..

7.7.	Inspect the gear tooth contact pattern of the pinion and the ring gear. Refer to Gear Tooth Contact Pattern Inspection.

7.8.	If the gear tooth pattern is still incorrect, adjust the shim thickness as necessary and recheck the gear tooth pattern of the pinion and the ring gear.

8. Inspect the backlash between the pinion and the ring gear and adjust, if necessary. Refer to Backlash Adjustment.

The pinion shims are available in the following sizes:

Shim Sizes