Cv- boots should also be checked regularly to ensure that there is no form of damage especially when the vehicle is serviced by replacing the oil and when the vehicle is elevated. These boots are also vital in avoiding the entry of water, grime, dirt and other dangerous substances in the CV joints since any contamination may cause premature CV-joint failure that is usually expensive to rectify. A tearing boot can be indicated by excessive grease outside the interior of the wheel(s) and also on the brake caliper or the brake drum. One should also carefully examine clamps and tears that are not present and in case of any damage, the replacement of the boot should be done immediately. Mazda suggests that the CV-boots should be checked after every 30,000 miles (48,000 km).