Side bearing preload is necessary to maintain the correct bearing pressure on both sides of the differential case so that the differential case will turn evenly at all speeds. Side bearing preload is measured by the distance between the side bearing caps or case spread. Once the differential side bearing preload has been adjusted, it must be maintained throughout the differential backlash adjustment procedure. Setting differential backlash is very important to the service life of the ring and the pinion gears. Setting differential backlash determines the amount of depth at which the ring gear will contact the pinion gear. This determines the distance of the pinion gear teeth from the drive side and the coast side of the ring gear teeth. The deeper the gears mesh, the less amount of backlash. The more shallow the mesh, the more backlash is created. This adjustment is vital for correct differential operation.

Tools Required

1. Use the J 37760 until it no longer makes contact with the right differential side bearing race in order to loosen the right differential side bearing adjuster (1).
2. Use the J 37760 until the ring gear is fully engaged with the pinion gear (0.000 backlash) in order to tighten the left differential side bearing adjuster.
3. Inspect the right adjuster. Ensure the right adjuster is not making contact with the right side bearing race.
4. Grasp the pinion flange and rotating the pinion gear several times in order to inspect the pinion gear for binding.



5. Install a J 8001 on the differential carrier between the center of each side bearing cap (1) to measure case spread.
6. Use a J 37760 until the adjuster makes contact with the right side bearing race in order to tighten the right adjuster.
7. Rotate the J 8001 adjustable face until the indicator needle reads 0.
8. Adjust the differential side bearing preload by tightening the right adjuster using J 37760 until the J 8001 reads 0.0508-0.1524 mm (0.002-0.006 in). This specification indicates the amount of case spread between the centers of both side bearing caps.