Rear Drive Axle and Differential

WARNING: This page is about a different car, the 2007 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.

The rear axle assembly contains the following:

An integral-type housing hypoid gear design (center of the pinion set below the centerline of the ring gear)
The hypoid differential ring gear and pinion consists of a 7.5-inch ring gear and an overhung drive pinion which is supported by 2 opposed tapered roller bearings
Pinion bearing preload is maintained by a drive pinion collapsible spacer on the differential pinion shaft and adjusted by the pinion nut
The axle housing assembly consists of a cast center section with 2 steel tube assemblies and a stamped differential housing cover
The differential housing cover uses silicone sealant as a gasket
The differential pinion shaft is retained by a threaded differential pinion shaft lock bolt assembled to the differential case
The differential case is mounted in the rear axle housing between 2 opposing differential bearings that are retained in the rear axle housing by removable bearing caps
Motorcraft 80W-90 Premium Rear Axle Lubricant XY-80W90-QL or equivalent meeting Ford specification WSP-M2C197-A is used in this assembly
Differential bearing preload and ring gear backlash are adjusted by differential bearing shims located between the differential bearing cups and the rear axle housing
Rear axle identification is on an embossed metal tag bolted to the differential housing cover

The rear drive axle receives rotational torque from the driveshaft. The direction of the rotation determines movement of the vehicle. The rotation enters the rear drive axle through the drive pinion flange, turning the drive pinion and rotating the ring gear. The ring gear is bolted to the differential case. The differential case houses the pinion shaft upon which the differential pinion gears ride. The pinion gears are in mesh with the differential side gears to which the axle shafts are splined. It is the unique arrangement of the differential that allows the axle shafts to be driven at different speed when needed, such as when driving around corners. A Traction-Lok® differential is also available that introduces a series of clutch plates and discs behind the differential side gears to deliver as much torque as possible to each axle shaft when the traction at the rear wheels is not equal. The Traction-Lok differential requires a friction modifier that must be install with the axle lubricant for the plates and discs to be functional.