The job of a CV joint is to transfer a constant speed of torque (rotational power) to the wheels via the driveshaft and to support up and down suspension motion. In the event of a CV joint failure you might notice a vibration during acceleration that stops as soon as you take your foot off the gas pedal. Alternatively you might feel a clunking sensation during a gear change, most noticeably when the reverse gear is engaged. It is fairly straightforward to diagnose a CV joint failure by examining the joint. If the CV boot is damaged (ripped or worn out), you should check the CV joint beneath the CV boot to make sure it feels greasy. If it does not, you will need to replace the CV joint itself. However, if the joint is still well lubricated it should only be necessary to replace the CV boot, using one of our kits.