The C/V joints are a very important part in the drivetrain, as they allow for articulation of the suspension, while continuously transferring power to the drive wheels. Due to the constant stress these C/V joints are under, they need to be kept well lubricated and protected from the elements.

That is where C/V boots come in. These boots protect the C/V joint while keeping a large amount of grease sealed around the C/V joint. However, since these boots are made of rubber and are exposed to the elements, over time they will become brittle and crack. Once this happens, they must be replaced in order to keep the C/V joint protected.