Checking Backlash

1. Mount a dial indicator with a magnetic base to the axle housing.
2. Place the indicator tip at the heel end of the tooth.
3. Check the backlash at three equally spaced points. The backlash should be 0.13-0.23 mm (0.005-0.009 inch) The measurement must not vary more than 0.05 mm (0.002 inch) between the points checked.
A. High backlash is corrected by moving the ring gear closer to the pinion,
B. Low backlash is corrected by moving the ring gear away from the pinion.
4. To adjust the backlash, the differential case must be removed from the housing, and the shims adjusted from one side to the other. For example: if the shim thickness needs to be reduced on the ring gear side by 0.13 mm (0.005 inch), then 0.13 mm (0.005 inch) must be added to the other side. If backlash is correct and the preload must be changed, then change each side by an equal amount.
5. Make the final gear pattern check.