All CV joints are encased in a protective rubber (neoprene, natural, or silicone) or thermoplastic (Hycrel)
boot. The job of the boot is to retain grease and to keep dirt and water out. The importance of the boot cannot be
over emphasized because without its protection the joint does not survive. For all practical purposes, a CV joint is
lubed for life. Once packed with grease and installed, it requires no further maintenance. A loose or missing boot
clamp, or a slit, tear or a small puncture in the boot it self allows grease to leak out and water or dirt to enter. consequently the joint is destroyed.