6-15.1. REAR AXLE DIFFERENTIAL MAINTENANCE (M1028A2) (Cont).
If ring gear (12) and drive pinion were replaced, perform steps 10-13 to
check for proper gear tooth contact pattern.
Wipe any lubricant from axle housing and clean each tooth of ring gear (12).
Using medium stiff brush, sparingly apply prussian blue dye to all ring gear (12) teeth. Area of
drive pinion tooth contact should be visible when drive pinion is turned by hand.
Excessive turning of ring gear (12) is not recommended. Ring gear should
be turned only enough to provide tooth contact pattern.
Apply load until it takes a torque of 40-50 Ib.-ft, (54-68 N.m) to turn drive pinion. Turn
companion flange so that ring gear (12) turns 1 full revolution, then reverse so that ring gear
turns 1 full revolution in opposite direction.
Contact pattern should be centrally located up and down on face of ring gear (12) teeth.
Compare tooth contact pattern on ring gear with examples shown and make adjustments as
indicated. (See paragraph 6-17.1, subparagraph c, steps 1-3)