DriverSide's Car Dictionary has the most comprehensive definitions of automotive terms. This auto glossary can help you decipher what your mechanic is fixing and what the purpose or function of the particular auto part or accessory is for. We have taken the mystery out of automotive service jargon, so that you don't have to.
You'll probably only hear about these "boots" when they tear--either from the clicking sound coming from the front end while turning, or a mechanic telling you they need replacing. They are simply rubber or plastic covers of ball joints that hold grease.