Rear Drive Axle and Differential

Rear Drive Axle and Differential

The rear drive axle consists of the following components:

- Dished circular flange
- Full-time Active Torque Coupling (ATC)
- Aluminum housing with steel housing cover
- Matched ring and pinion
- Conventional open differential
- Rubber bushing isolated mounting points
- Cover-mounted axle vent

The rear axle drive pinion receives power from the engine through the transaxle, Power Transfer Unit (PTU), driveshaft and ATC, and is always engaged. The All-Wheel Drive (AWD) system on this vehicle is equipped with a bar-coded rear axle to reduce the tolerance of electrical current-to-torque delivered by the ATC. The 4X4 control module uses this bar code information to match the clutch characteristics of the ATC with the desired output torque. The pinion gear then rotates the differential ring gear, which is bolted to the differential case outer flange. Inside the differential case, 2 differential pinion gears are mounted on a differential pinion shaft, which is pinned to the differential case. These differential pinion gears are engaged with the differential side gears to which the halfshafts are splined. The halfshafts are held in the differential case by a driveshaft bearing retainer circlip that is located on the inboard CV joint stub shaft pilot bearing housing. When each halfshaft is installed, the driveshaft bearing retainer circlip engages a step in the differential side gear. As the differential case turns, it rotates the halfshafts and rear wheels. When it is necessary for one wheel and halfshaft to rotate faster than the other, the faster turning differential side gear causes the differential pinion gears to roll on the slower turning differential side gear. This allows differential action between the 2 halfshafts. The pinion seal and the differential halfshaft seals are the only serviced components of the rear drive axle. There are no stub shaft bearings in the differential housing and the differential housing cover uses a silicone sealant rather than a gasket. If other components of the rear drive axle or the ATC are worn or damaged, a new axle assembly must be installed.