Axle Shaft: Description and Operation

DESCRIPTION
The front wheel driveshaft and joints are the mechanical link that transfers engine torque from the transaxle and differential to the front wheels. At the transaxle end, the LH front wheel driveshaft joint is splined to the differential side gear. Disengagement of the LH front wheel driveshaft joint from the differential side gear is prevented by an expanding spring steel driveshaft bearing retainer circlip. During installation the driveshaft bearing retainer circlip compresses around the LH front wheel driveshaft joint as it enters the differential side gear. Once through the differential side gear, the driveshaft bearing retainer circlip expands into a counterbore machined into the back side of the differential side gear. The RH front wheel driveshaft and joint is secured by the front axle bearing bracket.

VEHICLE ATTACHMENT
The wheel ends of the front wheel driveshaft and joints are splined to the wheel hubs which are supported on front wheel bearings. Disengagement of the front wheel driveshaft and joint from the wheel hub is prevented by a staked front axle wheel hub retainer. Backlash between the wheel hub and front wheel driveshaft and joint is eliminated by the splines. The wheel hub splines are machined straight, and the front wheel driveshaft and joint splines are machined with a slight helical cut. The difference in splines provides a tight, backlash-free coupling without the removal and installation problems associated with an interference fit.

JOINT DESCRIPTION
All outboard front wheel driveshaft joints are the Birfield-type. Vehicles with automatic transaxles are equipped with tripot-type inboard front wheel driveshaft joints. Vehicles with manual transaxles are equipped with double offset inboard front wheel driveshaft joints. The tripot-type front wheel driveshaft joints are used with the automatic transaxles to prevent the transfer of engine vibration through the front wheel driveshaft and joint to the vehicle body. A front axle bearing is installed between the RH front wheel driveshaft and joint and the halfshaft to help prevent engine vibration to the vehicle body and reduce torque steer.

OPERATION
The front wheel driveshaft joints transmit torque while compensating for front suspension movement. As the suspension moves, the front wheel driveshaft joint allows the front wheel driveshaft and joint to change effective length and to operate smoothly through varying angles. For the necessary flexibility, the double offset and Birfield-type front wheel driveshaft joints use ball bearings positioned by a bearing cage. The tripot-type front wheel driveshaft joint uses three balls mounted on needle bearings and a spider. In both types of front wheel driveshaft joints, the outer race is machined into the front wheel driveshaft joint housing.

SERVICING
The double offset and tripot-type front wheel driveshaft joints can be disassembled and serviced. Other than the front wheel driveshaft joint boot, the outboard Birfield-type front wheel driveshaft and joint is serviced only as an assembly with the front wheel driveshaft and joint.

NOTE: Read and follow all handling precautions.