Drive Axles, Bearings and Joints: Description and Operation

DESCRIPTION





Vehicles equipped with either an automatic or manual transmission use an unequal-length halfshaft system. The system incorporates two halfshaft assemblies (left and right) that consist of an inner and outer Constant Velocity (CV) joint and a solid interconnecting shaft (Fig. 1). The right halfshaft is longer than the left due to transaxle packaging and powertrain design.

Halfshafts 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 halfshaft is located on and the transmission application of the vehicle. When replacing a halfshaft, be sure the replacement halfshaft has the same damper weight as the original.

Both halfshaft assemblies use the same type of inner and outer joints. The inner joint of both halfshaft assemblies is a tripod joint, and the outer joint of both halfshaft assemblies is a Rzeppa joint. Both tripod joints and Rzeppa joints are true Constant Velocity (CV) joint assemblies. The inner tripod joint allows for the changes in halfshaft length through the jounce and rebound travel of the front suspension.

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





The inner tripod joint of both halfshafts 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 CV joint has a stub shaft that is splined into the wheel hub and retained by a hub nut, nut lock, wave washer and cotter pin (Fig. 2).

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 C/V 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 C/V joint and the wheel bearing area In the steering knuckle before it is assembled after servicing.

OPERATION
Halfshaft assemblies are designed to transmit power from the transaxle to the front wheels, while allowing for powertrain and suspension flex.