“What are CV boots?”
CV Boots are the protective rubber boots that cover the constant velocity joints (or “CV joints”) on a vehicle’s drive axles and contain the lubricating grease that’s vital to the operation and longevity of the CV joint and axle. Over time, normal wear and tear can rip openings in the boot, exposing the CV joint inside. When that happens, the rotational force of the spinning axle and joint will sling the grease out through the torn CV boot while simultaneously allowing harmful contaminants and road grit to get in.
(Click images to view larger version)
“Are there any symptoms of torn CV boots?”
Unfortunately, there are no noises or drive-ability issues until after the problem has been neglected long enough and the CV joint itself has become damaged. This is why it is so critical to have your CV boots inspected every time your vehicle is in for service and to replace them at the first sign of tearing. When caught early, it is a relatively minor and low-cost repair to replace CV boots. We can replace them with a new CV boot kit, like we did with the front-outer CV boots on this ’04 Porsche 996 C4S. We removed the torn boots, thoroughly cleaned the joint and surrounding components, repacked them with fresh grease, and installed brand new boots and clamps to ensure a tight seal.
Porsche 996 CV Boot Replacement Kit
“What happens if I don’t replace torn or damaged CV boots?”
If not caught and replaced in time, a torn CV boot can lead to ruined CV joints. In many cases, including the 996 pictured here, replacement CV joints are only offered as a packaged kit with the full axle assembly which is significantly more expensive than the cost of replacing just the boots. Again, this is why it is very important to have your CV boots inspected regularly during normal service visits to prevent axle failure and avoid the increased expense of replacing the CV joint and axle.
If you own a four-wheel drive Porsche, it should be noted that it is very common for the front-outer CV boots to be more susceptible to tearing. Similarly, torn inner-rear CV boots are a common issue with Porsche Boxsters. Due to the mid-engine layout of the Boxster, the inner-rear CV boots are located very close to a portion of the exhaust system. The intense heat from the exhaust is known to accelerate the wearing process of the rubber and shorten the life-span of the boots.