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| CV Joints and FWD Axles |
The typical FWD axle consists of a half shaft with an inner joint, an outer joint, and a
torsional damper in the center. The most common failure of this type of axle is a worn
or damaged outer or CV (constant velocity) joint.
The CV joint allows the axle to apply torque to the wheel while cornering due to its
unique ball bearing design. The most common type of outer joint is called a Rzeppa
joint. The boots that contain the grease required to keep these joints operating
smoothly tend to wear leaving them exposed to the environment.
Worn or damaged Outer CV joints make a clunking or clicking noise particularly when
cornering. It’s more noticeable on the inside wheel of the turn. A worn right front or
passengers side CV joint would make the most noise when the vehicle is turning right.
This clicking noise is usually even more noticeable in reverse.
The joint is serviceable by removing the boot clamp, pulling the boot away, and
removing a snap ring or a circle clip from the shaft. Then carefully tap on the outside of
outer bearing race with a soft hammer.
After cleaning the parts which include 6 ball bearings, inner bearing race, a bearing
cage, and the outer bearing race, carefully inspect these parts for damage and wear.
When rebuilding this joint always pack this bearing cage completely with the grease
supplied in the kit and then fasten the boot tightly.
The inner joint consists of the tulip and the tripod assembly. This joint provides the axle
torque and in and out movement while the vehicle travels over bumps in the road.
Excessive vibration during acceleration and deceleration indicates a problem with the
inner joint. This joint is serviced similar to the outer joint. A loose, damaged, or missing
torsional damper will also cause a shudder or vibration while traveling at certain
speeds.
torsional damper in the center. The most common failure of this type of axle is a worn
or damaged outer or CV (constant velocity) joint.
The CV joint allows the axle to apply torque to the wheel while cornering due to its
unique ball bearing design. The most common type of outer joint is called a Rzeppa
joint. The boots that contain the grease required to keep these joints operating
smoothly tend to wear leaving them exposed to the environment.
Worn or damaged Outer CV joints make a clunking or clicking noise particularly when
cornering. It’s more noticeable on the inside wheel of the turn. A worn right front or
passengers side CV joint would make the most noise when the vehicle is turning right.
This clicking noise is usually even more noticeable in reverse.
The joint is serviceable by removing the boot clamp, pulling the boot away, and
removing a snap ring or a circle clip from the shaft. Then carefully tap on the outside of
outer bearing race with a soft hammer.
After cleaning the parts which include 6 ball bearings, inner bearing race, a bearing
cage, and the outer bearing race, carefully inspect these parts for damage and wear.
When rebuilding this joint always pack this bearing cage completely with the grease
supplied in the kit and then fasten the boot tightly.
The inner joint consists of the tulip and the tripod assembly. This joint provides the axle
torque and in and out movement while the vehicle travels over bumps in the road.
Excessive vibration during acceleration and deceleration indicates a problem with the
inner joint. This joint is serviced similar to the outer joint. A loose, damaged, or missing
torsional damper will also cause a shudder or vibration while traveling at certain
speeds.
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