Final Assembly & Adjustment

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, five to ten times, after each adjustment.

Fig. 21 Ring Gear & Pinion Backlash Check:

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 four 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 0.003-0.004 inch at indexed tooth with bearing adjusters torqued to 10 ft. lbs., seating side bearing races as outlined previously.
9. Torque bearing cap bolts as follows:
a. On 7 1/4 inch ring gear, 45 ft. lbs.
b. On 8 1/4 inch ring gear, 100 ft. lbs.
c. On 8 3/8 inch ring gear, 70 ft. lbs.
d. On 9 1/4 inch ring gear, 100 ft. lbs.
10. Torque right adjusting nut to 70 ft. lbs., then seat bearings by tightening right adjuster and oscillating pinion to seat bearings until torque at right adjuster remains constant at 70 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 70 ft. lbs. Torque of left bearing adjuster should be approximately 70 ft. lbs. after performing above procedures. If torque value is substantially less than 70 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 locks are properly engaged in adjuster teeth, then torque lock bolts to 90 inch lbs.
14. If side bearings and thrust washers were replaced during differential overhaul, check differential side gear clearance as follows:
a. When measuring side gear clearance, check each gear independently.
b. Install axle shafts and C-clips locks and pinion mate shaft.

Fig. 22 Side Gear Clearance Measurement:

c. Measure each side gear clearance by inserting a matched pair of feeler gauge blades between gear and differential housing on opposite side of hub.
d. If side gear clearances does not exceed 0.005 inch. Check if shaft is contacting pinion gear mate shaft. Do not remove feeler gauges. If end of axle shaft is not contacting pinion gear mate shaft, side gear clearance is acceptable.
e. If clearance is more than 0.005 inch (axle shaft not contacting mate shaft), record side gear clearance. Remove thrust washer and measure its thickness. Add washer thickness to recorded side gear clearance. Sum of gear clearance and washer thickness will determine required thickness of replacement thrust washer.
f. In some cases, end of axle shaft will move and contact mate shaft when feeler gauge is inserted. C-clip lock is preventing side gear from sliding on axle shaft.
g. If there is no side gear clearance, remove C-clip from axle shaft. Remove thrust washer, measure and record thrust washer thickness, then reinstall thrust washer. Assemble differential case without C-clip installed and re-measure side gear clearance.
h. Compare both clearance measurements. If difference is less than 0.012 inch, add clearance recorded when C-clip was installed to thrust washer thickness measured. Sum will determine required thickness of replacement thrust washer.
i. If clearance is 0.012 inch or greater, both side gears must be replaced (matched set) and clearance measurements repeated.
j. If clearance continues to be 0.012 inch or greater, case must be replaced.
15. Coat coast and drive face of each ring gear tooth with suitable marking compound.
16. 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. 23 Gear Tooth Contact Inspection:

17. Contact pattern should be centered on ring gear teeth as shown.
18. 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.
19. Ensure 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.
20. Install anti-lock brake sensor and torque retaining bolt to 170-230 inch lbs.