Final Assembly & Adjustment

Fig. 7 Typical side bearing adjustment:

Fig. 20 Ring gear & pinion backlash check:

DIFFERENTIAL, INSTALL
1. Coat side bearings, races and bearing adjusters with specified lubricant.
2. Place side bearing races over respective bearings, then install and support differential assembly in housing.
3. Install side bearing caps in proper locations, torque top cap bolts to 10 ft. lbs. and tighten bottom bolts hand tight.
4. Tighten each bearing adjuster until side bearing endplay is reduced to zero, maintaining approximately 0.010 inch backlash between ring gear and pinion. Side bearing caps will not always move directly with adjusters. In order to ensure accurate adjustment changes and to maintain proper gear mesh, seat bearings by oscillating drive pinion 1/2 turn in each direction, 5 to 10 times, after each adjustment.
5. Mount suitable dial indicator with plunger at right angle to ring gear tooth and contact button bearing against tooth.
6. Hold pinion, rock ring gear back and forth and note backlash reading on dial indicator.
7. Check backlash at 4 evenly spaced positions around ring gear, index tooth at position where least backlash is observed and make all further checks at this position. Backlash variation of up to 0.003 inch between minimum and maximum readings is acceptable. If backlash variation exceeds 0.003 inch, recheck ring gear mounting, and ring gear and case, runout, and correct as needed.
8. Loosen right adjuster and tighten left adjuster until backlash is 0.003---.004 inch at indexed tooth with bearing adjusters torqued to 10 ft. lbs., seating side bearing races as outlined previously.
9. Torque bearing cap bolts to 100 ft. lbs. (1986---87 models with 8 3/8 inch ring gear, 70 ft. lbs.) and right adjusting nut to 75 ft. lbs., then seat bearings as outlined.
10. Continue tightening right adjuster and oscillating pinion to seat bearings until torque at right adjuster remains constant at 75 ft. lbs.
11. Measure backlash at indexed tooth. If backlash is not within specifications, continue tightening right adjuster and seating bearing races until proper lash is obtained.
12. When proper backlash is obtained, check and adjust torque of left bearing adjuster to 75 ft. lbs. Torque of left bearing adjuster should be approximately 75 ft. lbs. after performing above procedures. If torque value is substantially less than 75 ft. lbs., loosen bearing caps and side bearing adjusters and repeat complete adjustment procedure in order to obtain proper side bearing preload at specified backlash.
13. Install adjuster locks ensuring that locks are properly engaged in adjuster teeth, then torque lock bolts to 90 inch lbs.
14. Coat coast and drive face of each ring gear tooth with suitable marking compound.
15. Apply braking force to differential case and turn pinion to rotate ring gear one full revolution in each direction. If gears are not loaded, accurate contact pattern cannot be obtained.

Fig. 21 Gear tooth contact inspection:

16. Contact pattern should be centered on ring gear teeth as shown.
17. If contact pattern is located at heel end (inside) of gear, pinion shim thickness should be increased to center pattern. If contact pattern is located at toe end (outside) of gear, decrease pinion shim thickness to center pattern. Slight modifications in ring gear and pinion backlash may also be necessary to center contact pattern. However, backlash must be kept within specified limits in order to provide necessary operating clearance.
18. Ensure that bearing adjuster locks are properly installed, then install axle shafts, rear cover and propeller shaft, and fill axle with specified lubricant. If RTV sealer is used to seal rear cover, apply a continuous bead of sealer to cover, 1/8 inch wide, circling all bolt holes.