Pinion Depth & Bearing Preload
- If original parts are reinstalled, use the same thickness pinion depth and bearing preload adjusting shims as were removed. If a new ring and pinion gear set is installed, new adjusting shims must be selected.
- Press new pinion shaft bearing outer races into final drive housing and pinion cover until they are fully seated. Install new pinion oil seal into final drive case. Install new oil seal into final drive side of pinion cover with open side of seal towards final drive housing, then install a new oil seal into transaxle side of pinion cover with open side towards transaxle.
- Heat pinion shaft bearings to 212°F (100°C) in hot oil. Install both bearings (without shims) onto pinion shaft until they are seated.
- Install pinion shaft into final drive housing. Install pinion cover on housing, then install attaching bolts and tighten to 18 ft. lbs. (24 N.m).
- Attach a dial indicator onto final drive housing using holder (VW 387). See Fig 1 . Then, place measuring plate (VW 385/17) on end of pinion. Zero dial indicator without preload.
- Move pinion shaft up and down (without turning) and note dial indicator reading. To this reading add .004" (.10 mm) for bearing preload and .004" (.10 mm) for settling of bearings. The resulting sum is the total thickness of adjusting shims necessary for correct pinion depth and bearing preload adjustment. Record sum for future reference.
- Remove pinion shaft. Press bearing from near end of shaft. Select shims of correct thickness as determined in step 6 , and install them on gear end of shaft. Reinstall bearing onto shaft, then install shaft into final drive housing.
- Install setting gauge (VW 385/22) on pinion. See Fig 2 . Hold in place with spring support (VW 385/19).
- Adjust setting ring on measuring bar (VW 385/1), until distance from center of bar to outside of ring is approximately 2.9" (74 mm).
- Slide centering discs (VW 385/2) on measuring bar. Screw measuring pin (VW 385/14) into bar with .118" (3 mm) extension (VW 385/20).
- Screw left side differential side bearing adjusting ring into final drive housing until it is flush with housing. Place measuring bar assembly in final drive housing. See Fig 4 . Install right side bearing adjusting ring into final drive housing.
- Turn knob on end of measuring bar to move centering discs outward until bar can just barely be turned by hand. Attach a dial indicator to measuring bar. Place setting block (VW 385/21) on measuring bar. See Fig 4 . Zero dial indicator without preload. Remove setting block.
- Rotate measuring bar, until measuring pin rests against setting gauge on pinion face, then rotate bar back and forth over center. Read and record maximum dial indicator reading.
- Add the dial indicator reading just obtained to the deviation number stamped in ring gear. See Fig 5 . The resulting sum is thickness of pinion depth adjusting shim to use at reassembly.
- Next, subtract the thickness of pinion depth shim just selected from the total pinion adjusting shim thickness obtained in step 6 . The remainder is thickness of pinion bearing preload shim to use at reassembly.
- Remove measuring tools and pinion shaft from final drive housing. Press bearings from pinion shaft. Install the selected pinion bearing preload shim onto gear end of pinion shaft, then press bearing back onto shaft. Place the selected pinion depth shim on opposite end of shaft, then press remaining bearing onto shaft along with pinion oil seal bushing.
- Install pinion shaft into final drive housing and lubricate bearings with hypoid gear oil. Reinstall measuring bar into housing and zero dial indicator with .04" (1.0 mm) preload.
- Recheck pinion depth and bearing preload adjustment. If correct shims have been installed, dial indicator reading should be equal, to the ring gear deviation number with a tolerance of plus or minus .0016" (.04 mm). Remove measuring bar and side bearing adjusting rings.
- Finally attach a torque wrench to pinion shaft and check pinion shaft turning torque. Turning torque should be at least 12.4 INCH lbs. (1.4 N.m).
NOTE:
For correct pinion depth and bearing preload adjustment, measuring tools called out in the following procedures must be used.
NOTE:
Refer to Fig 3
for the assembling of tools to measuring bar.
NOTE:
The ring gear deviation number is in hundredth millimeters.
NOTE:
Pinion depth and bearing preload shims are available in thicknesses from .043" (1.1 mm) to .075" (1.9 mm) in increments of .001" (.025 mm). Also, shim thickness should be measured at several points on shim prior to installation to ensure correct thickness shims are being installed.
NOTE:
Turning torque value given is for new bearings only. If used bearings are installed, turning torque should be measured prior to final drive disassembly. When assembled correctly, turning torque with used bearings should be approximately 1.7-3.5 INCH lbs. (.2-.4 N.m) greater than it was prior to disassembly.