Suburban 3/4 Ton 4WD V8-305 5.0L (1986)
10.
If pinion was not removed, check backlash and tooth pattern as follows:
a. Apply suitable marking compound on ring gear teeth.
b. Rotate drive pinion one revolution and check gear tooth contact pattern as shown on Fig. 4. Add or remove shims as required.
c. After backlash and tooth pattern operation has been completed, remove shim packs using caution not to mix them.
d. Select new shims for each side .004 inch thicker than those removed, then install each shim on its proper side. This additional thickness will
ensure proper bearing preload.
e. Check total rotational torque. Total torque with differential case preloaded and pinion installed should be 16---29 inch lbs. if new bearings
are installed or 10---16 inch lbs. if original bearings are installed.
f.
If total rotational torque is not as specified, repeat steps 4 through 10.
11.
If drive pinion was removed, remove differential case and shims, then proceed to ``Drive Pinion & Bearing Shim Adjustment'' procedure.
4 - Pinion
Fig. 3 Installing shims
To adjust differential side bearing preload, change thickness of right and left shims equally so original backlash is not disturbed.
1.
Ensure side bearing surfaces are clean and free of burrs.
2.
Apply suitable lubricant to side bearings. If original bearings are to be reused, original outer races should also be used.
3.
Install differential case in carrier, with bearing outer races in position.
4.
Install left bearing cap and cap attaching bolts loosely so case may be moved during adjustment.
5.
Measure original spacers and subtract .004 inch from each reading. Use caution not to interchange right and left spacers.
6.
Select a service spacer for each side equal to thickness of original shim minus .004 inch, then install shim as shown in Fig. 3. Ensure flat edge of
spacer faces against housing.
7.
At this point, bearings should have no play and no drag (zero preload). If zero preload is not present, shims should be added or removed equally
from both sides as necessary.
8.
Check case for zero endplay using a dial indicator. If shim installation causes excessive pinion to ring gear clearance, select thinner left shim
and add difference to right side. Keep total shim thickness at a value equal to that obtained in step 6.
9.
Install both bearing caps and cap attaching bolts. Torque bolts 40 ft. lbs.
