Axle Shaft: Description and Operation

Vehicles equipped with either an automatic or manual transmission use an unequal-length driveshaft system.

Fig. 1:

The system incorporates two driveshaft assemblies (left and right) that consist of an inner and outer Constant Velocity (CV) joint and a solid interconnecting shaft (Fig. 1). The right driveshaft is longer than the left due to transaxle packaging and powertrain design.

Driveshafts used on both the right and left sides of the vehicle use a tuned rubber damper weight mounted to the interconnecting shaft (Fig. 1). The damper weight applications vary by which side of the vehicle the driveshaft is located on and the transmission application of the vehicle. When replacing a driveshaft, be sure the replacement driveshaft has the same damper weight as the original.

Both driveshaft assemblies use the same type of inner and outer joints. The inner joint of both driveshaft assemblies is a tripod joint, and the outer joint of both driveshaft assemblies is a Rzeppa joint. Both tripod joints and Rzeppa joints are true constant velocity (C/V) joint assemblies. The inner tripod joint allows for the changes in driveshaft length through the jounce and rebound travel of the front suspension.

On vehicles equipped with ABS brakes, the outer C/V joint is equipped with a tone wheel used to determine vehicle speed for ABS brake operation.

Fig. 2:

The inner tripod joint of both driveshafts is splined into the transaxle side gears. The inner tripod joints are retained in the side gears of the transaxle using a snap ring located in the stub shaft of the tripod joint. The outer C/V joint has a stub shaft that is splined into the wheel hub and retained by a single piece steel hub nut (Fig. 2). The hub nut is a locking style; the nut lock, anti-rattle washer, and cotter pin are not necessary.

NOTE: This vehicle does not use a rubber-lip bearing seal as on previous front-wheel-drive cars to prevent contamination of the front wheel bearing. On these vehicles, the face of the outer CV joint fits deeply into the steering knuckle, using a close outer CV joint-to-steering knuckle fit. This design deters direct water splash on bearing seal while allowing any water that gets in, to run out the bottom of the steering knuckle bearing bore. It is important to thoroughly clean the outer CV joint and the wheel bearing area in the steering knuckle before it is assembled after servicing.