Differential Assembly: Adjustments

CORVETTE
1. Ensure differential case flange is free of nicks and burrs, then install ring gear on case using new bolts. Torque attaching bolts to 45---60 ft. lbs. on 1982 Corvette, 70---90 ft. lbs. on 1984 Corvette or 75---85 ft. lbs. on 1985---87 Corvette models. Tighten bolts evenly so that ring gear will be properly seated on case.
2. On 1982 models, install master differential bearings J-29538 onto differential case. On 1984---87 models, install master differential bearings J-34170 on 7.874 inch axles or J-35505 on 8.5 inch axles.
3. Assemble case assembly into carrier. Mount suitable dial indicator to supporting fixture.
4. Force differential case away from pinion gear until completely seated against carrier cross bore face. With force still applied to case, place dial indicator plunger on a flat machined surface of differential case, if available, or on the head of a ring gear screw. Zero dial indicator.
5. Force ring gear to mesh with drive pinion. Rock gear slightly to ensure gear teeth are meshed and note dial indicator reading. Repeat procedure several times to ensure the reading is accurate. Ensure dial indicator reads zero each time the case is seated against cross bore face. The reading, minus .005 inches on 1982---84 models or .006 inch for 1985---87 models for preload and backlash adjustment will be the size of the shim pack between differential case and differential bearing on ring gear side.
6. Remove dial indicator, differential case and master bearings.
7. Assemble shim pack as determined in step 5 above to ring gear side hub, then install bearing cone.
8. Take measurement obtained during ``Differential Side Bearing Preload Adjustment'' and subtract shim pack dimension determined in step 5 above. To the resulting dimension, add .009 inch to 1982 models, .015 inch to 1984 models, .015---.020 inch to 1985---87 models with 7.874 inch axle or .008---.012 inch to 1985---87 models with 8.5 inch rear axle.
9. Assemble shim pack as determined in step 8 above to hub opposite ring gear, then install bearing cone.

Fig. 3 Spreader tool installation. Corvette models:

10. Install spreader tool, J-24385-01, adapter, J-24385 and suitable dial indicator set, Fig. 3.Zero indicator and ensure indicator stylus contacts one side of housing opening.
11. While observing micrometer, spread housing with tool. Do not spread housing more than 0.010 inch or distortion could result.
12. Assemble differential bearing cups on case, then install case in rear housing. If necessary, use a suitable soft faced hammer to seat case in carrier cross bore.
13. Install bearing caps and bolts. Ensure letters stamped on caps correspond in position and direction with letters stamped in carrier. Torque bolts to 60---70 ft. lbs. on 1982 models, 40---50 ft. lbs. on 1984 models, 42---48 ft. lbs. on 1985---87 models with 7.874 inch rear axle or 58---68 ft. lbs. on 1985---87 models with 8.5 inch rear axle.
14. Check ring gear and pinion backlash at three equally spaced points with suitable dial indicator. Backlash tolerance is .005---.009 on 1982 models, .005---.008 on 1984 models and .006---.009 on 1985---87 models. Backlash cannot vary between points checked more than .003 inch on 1982---84 models or .001---.0015 on 1985---87 models.
15. If backlash is excessive, move shims from side opposite ring gear to ring gear side, but do not change the combined total thickness of both shim packs.
16. If backlash is too small, move shims from ring gear side to side opposite ring gear, but do not change the combined total thickness of both shim packs.
17. Install inner yoke shafts into carrier, then the shaft snap rings. Check axle shaft endplay. If endplay is not within .0005---.0085 inch, install thicker or narrower axle shaft snap ring as necessary.
18. Install axle housing cover with RTV or gasket to rear housing and install bolts.
19. Install rear axle assembly. Refer to ``Rear Axle, Propeller Shaft & Brakes'' for procedure.
20. Add four ounces of limited slip additive No. 1052358 or equivalent to rear axle, then top off with rear axle lubricant No. 1052271 or equivalent.