Pinion Depth Adjustment

^ Tools Required:
- J 21777-40 Rear Pilot Washer
- J 21777-42 Front Pilot Washer
- J 21777-43 Stud Assembly Bolt
- J 21777-45 Side Bearing Discs
- J 23597- 1 Arbor
- J 23597-11 Gauge Plate
- J 8001 Dial Indicator

1. Clean all the gauge parts.








2. Lubricate the front and rear pinion bearings with axle lubricant.
3. Place the bearings into the pinion bearing cups.
4. Install J 21777-40, J 21777-42, J 21777-43, and J 23597-11 to the pinion bore.
5. Hold the stud stationary at the flats of the stud.
- Tighten stud nut to 2.2 Nm (20 inch lbs.).
6. Rotate the gauge plate and bearings several complete revolutions to seat the bearings.
7. Tighten the stud nut until a torque of 1.6 to 2.2 Nm (15 to 25 inch lbs.) is obtained to keep the gauge plate in rotation.
8. Assemble J 21777-45, J 23597-11, and J 8001 to the differential bearing bores as shown.
- The bearing bores must be clean and burr free.
9. Install the side bearing caps and tighten the bolts.
- Tighten bolts to 75 Nm (55 ft. lbs.).
10. Rotate the gauge plate until the gaging areas are parallel with the discs.
11. Position the gauge shaft assembly in the carrier so that the dial indicator rod is centered on the gauge area of the gauge block.
12. Set the dial indicator at zero. Push the indicator down on the indicator shaft until the needle rotates approximately 3/4 of a turn clockwise. Tighten the dial indicator in this position.
13. Rotate the gauge shaft slowly back and forth until the dial indicator reads the greatest deflection. This is when the indicator needle is centered between moving to the left and to the right.
14. At the point of greatest deflection, set the dial indicator to zero. Repeat the rocking action of the gauge shaft to verify the zero setting.
15. Rotate the gauge shaft until the dial indicator rod does not touch the gauge block.
16. Record the actual number on the dial indicator and not the number that represents how far the needle travels. This is the nominal pinion setting.





- EXAMPLE: if the indicator needle moved counterclockwise 1.70 mm (0.067 inch) to a dial reading of 0.84 mm (0.033 inch) as shown, record the dial reading of 0.84 mm (0.033 inch) NOT 1.70 mm (0.067 inch). The dial indicator should be in the 0.50 to 1.27 mm (0.020 to 0.050 inch) range.
17. All drive pinion gears are manufactured to a nominal depth. There are no markings on the pinion for depth. Dial indicator reading is the shim selection.
18. Remove bearing caps and depth gaging tools.
19. Install the correct pinion shim to the pinion.