Constant-velocity joints (CV joints) allow a drive shaft to transmit power through a variable angle, at constant rotational speed, without an increase in friction or play. They are mainly used in front wheel drive vehicles, and many modern rear wheel drive cars with independent rear suspension typically use CV joints.
CV joints are protected by a rubber boot, usually filled with grease. Cracks and splits in the boot will allow contaminants in, which would cause the joint to wear quickly. CV boots serve a simple but important purpose and allow the CV axles and joints to stay clean and enjoy a long service life. If you notice or suspect that your CV boot may be damaged, have a professional technician inspect the vehicle to determine if a CV boot replacement is appropriate, or if the entire CV joint should be replaced
Common failure symptoms:
- Grease leak. When the CV boot cracks or tears, it will usually leak grease on the inside of the wheel and possibly even “fling” grease onto the chassis or other parts of the undercarriage.
- Vibrations coming from a wheel could be caused from a failing CV axle. Dirt and debris can get into the CV joint causing damage creating the vibration. Vibrating CV axles will need to be replaced.
- Clicking noises, especially during turns. This is a symptom the CV joint has come loose and have excess play creating the noise. A clicking CV joint will need to be replaced.