Adjusting Backlash

NOTE: The backlash to be set is embossed on the ring gear.

1. Mount gear set using shims "S3" determined while adjusting the drive pinion.

NOTE: Make sure that the collar nut of the drive pinion is tightened to 300 Nm (221 ft lb) before measuring backlash.

2. Insert differential with tapered roller bearing and shims (S1 + S2) into the housing.
3. Fit lateral transmission cover and tighten all hexagon-head nuts to 23 Nm (17 ft lb).

NOTE:
- Always make sure that there is a certain amount of backlash when tightening the nuts.
- Never allow the drive pinion to seize.





4. Assemble measuring lever VW 388 and adjusting device VW 521/4 and adjust lever length to 80 mm with the plunger.
- Refer to dimension "a" in the illustration.
5. Insert adjusting device with clamping sleeve (Special Tool 9145) into the differential and clamp firmly.
6. Rotate differential in both directions several times to settle the tapered roller bearings.
7. Fit universal dial gauge holder with flat extension in such a way as to produce a right angle between dial gauge axis and lever.
8. Turn ring gear carefully at the clamping screw of the adjusting device as far as the stop and set the dial gauge to zero.
- Turn back ring gear and read off circumferential backlash.
- Note down the reading.





NOTE: When carrying out measurements, the drive pinion must be blocked with Special Tool 9562.

9. After turning the ring gear a further 90°, repeat measuring procedures three times.
- The measured values must not deviate from one another by more than 0.03 mm.

NOTE:
- The backlash to be adjusted is embossed on the ring gear.
- A deviation of ± 0.03 mm is permissible

10. If the required backlash cannot be obtained, replace spacers (S1 + S2) again.
- The total shim thickness ("S tot.") must not be altered, however.