Differential Assembly: Description and Operation

Fig. 1 Rear axle cross section:

The rear axle, Fig. 1, is a semi-floating type consisting of a cast carrier and large bosses on each end into which two welded steel tubes are fitted. The carrier contains an overhung hypoid pinion and ring gear. The differential is a two pinion arrangement.
The overhung hypoid drive pinion, is supported by two pre-loaded tapered roller bearings. The pinion shaft is sealed by means of a molded, spring loaded, rubber seal. The seal is mounted on the pinion shaft flange which is splined and bolts to the hypoid pinion shaft.
The ring gear is bolted to a one piece differential case and is supported by two pre-loaded tapered roller bearings.
A rear axle extension housing is bolted to the axle housing and is attached to the underbody by a center bearing support. An extension shaft inside the housing is splined to the drive pinion at the rear end and to the companion flange at the forward end.

Fig. 2 Rear axle assembly:

REPLACEMENT
1. Raise vehicle on a hoist.
2. Place adjustable lifting device under axle.
3. Disconnect rear shock absorbers from axle and remove propeller shaft and extension housing, Fig. 2.
4. Remove both rear wheels.
5. Retract shoes and remove right and left brake drums.
6. Disconnect brake lines from clips on axle tubes.
7. Disconnect track and stabilizer bars from axle tube.
8. Remove differential cover and drain lubricant.
9. Unscrew differential lock screw, remove pinion shaft and axle shaft ``C'' locks. Reinstall pinion shaft and tighten lock screw to retain differential gears.
10. Remove both axle shafts.
11. Remove brake backing plate retaining nuts and remove backing plates, with shoes and brake lines attached, and wire to frame.
12. Remove right and left lower control arm pivot bolts at axle.
13. Lower axle assembly slowly until coil spring tension is released, then remove axle.
14. Reverse procedure to install.