Rear Axle Description

The rear axle assembly contains two rigid axle shafts which transfer engine torque to the rear wheels. These axle shafts (2) are supported in the rear axle housing (1) by bearings (4) at both outer ends, and driven by the differential assembly which is mounted in the center of the rear axle housing. A propeller shaft turns the differential assembly and transfers power to the rear axle shafts. The rear axle housing is sealed and contains a synthetic gear lubricant which lubricates the differential assembly and axle shafts bearings. The rear axle housing is also vented to prevent excessive heat buildup.

The rear trailing rods connect the rear axle housing to the frame and act as pivot points for the housing as it moves up and down with the rear suspension. Coil springs support the rear of the vehicle and are seated into the frame and rear axle housing axle. Shock absorbers are fitted between the rear axle housing and the frame to help to reduce road vibration and rough pavement. An upper control arm is fitted to the body by bushings, and to the rear differential carrier by a rear control arm ball joint to prevent the rear axle housing from moving in a lateral direction.





The differential assembly uses a hypoid, beveled ring and pinion gear set. It consists of a ring gear (12) which is mounted to the differential case (9) and a pinion gear (1) which is mounted in the differential carrier (2). The ring and pinion gears are in constant mesh with each other. A set of six gears are mounted inside the differential case. Two of these gears are known as side gears (10) and the other four are known as differential pinion gears (111). Each side gear is splined to an axle shaft (5) which causes each axle shaft to turn when its side gear rotates.

The differential pinion gears are mounted on a pinion cross shaft (8) and are free to rotate on it. The pinion shaft is fitted into a bore in the differential case and is held in place by a pinion shaft roll pin. The differential case is mounted in the differential carrier where the pinion gear drives the ring gear, differential case, and the side and differential pinion gears. The differential carrier is mounted near the center of the rear axle housing. For removal and installation procedures, refer to Differential Replacement in Service and Repair.