Adjusting Pinion
Adjusting Pinion1. Heat pinion bearing inner race (large bearing) to about 100°C/212°F, install on pinion without shim and press on with a force of about 3 tons.
2 Heat pinion bearing inner race (small bearing) to about 100°C/212°F, install on pinion with 1.1 mm thick shim (arrow) and press on with force of about 3 tons.
Note: Pinion would hit housing while measuring and cause incorrect readings, if shim is omitted.
3. Install final drive housing cover without seals. Tighten all bolts to specified torque.
4. Install pinion and pinion cover. Tighten all bolts to specified torque.
5. Place VW 387 on housing and VW 385/17 on pinion. Install dial gauge and adjust to zero.
6. Move pinion up and down without turning it several times and note dial gauge reading.
Note: Readings would be wrong if pinion is turned.
7. Add 1.1 mm for installed shims, 0.15 mm for bearing preload and 0.10 mm for bearing settling to dial gauge reading.
This results in S tot
Example:
Dial gage reading 1.81mm
Installed shim +1.10mm
Bearing preload +0.15mm
Bearing settling +0.10mm
Total shim thickness = 3.16mm
8. Remove pinion. Take out installed shim (1.1 mm) and install shims of total thickness (3.16 mm in example) at small bearing.
9. Install pinion again and check deviation "e". Deviation "e" is the difference between the actual measurement r and the design measurement Ro.
10. Turn pinion in both directions several times.
11. Place VW 385/28 on pinion.
12. Set adjusting ring of VW 385/1 at distance a. a = approx. 82 mm.
13. Assemble VW 385/1 according to figure (dial gauge extension VW 385115 = 9.3 mm). Install VW 385/30 and set dial gauge at zero with 3 mm pre load.
14. Screw adjusting ring (opposite ring gear) into case far enough so that it is flush with housing.
15. Insert universal gauge in housing and screw in adjusting ring (behind ring gear). Do not place dial gauge pin on end gauge.
16. Pull 2nd centering disc outward with movable adjusting ring until universal gauge can just barely be turned by hand.
17. Turn universal gauge until dial gauge pin touches end gauge and shows maximum deflection (return point). Take dial gauge reading.
18. Note measured distance "e" (example: 1.88 mm) and determine thickness of shims S3 and S4.
19. Determine thickness of shim "S3". "S3 " = e - r
Example:
Dial gage reading "e" 1.88mm
Ring gear value "r" - 0.32mm
Thickness of shim "S3" 1.56mm
20. Select shims from table.
21. Determine thickness of shim "S4". "S4"= "S tot" - "S3"
Example:
Total shim thickness 3.16 mm
Shim thickness "S3" 1.56 mm
Shim thickness "S4" 1.60 mm
22. Select shims from table.
23. Check shim thickness at several positions with a micrometer. Check shims for burrs and damage. Only install perfect shims.
24. Install selected shims.
"S3" behind pinion.
"S4" opposite pinion.
25. Install pinion and lubricate bearings with hypoid gear oil.
26. Check measurements.
Install universal gauge. Set dial gauge at 0 with 3 mm preload. If proper shims have been installed, dial gauge reading must be specified deviation "r" within a tolerance of 0.04 mm (red gauge range).
27. After installation of pinion with the selected shims the turning torque must also be measured. It must be 250 to 550 Ncm (22-48 in. lb).
This value applies to new bearings. Measure actual turning torque before disassembly if used bearings are to be installed again.
A = US 1064 torque gauge, 0 - 600 Ncm (0 - 500 in. lb).