Your Automobile’s CV Joint Explained

Unless you are a trained mechanic, it is natural to be in the dark when it comes to some components of your car. Unfortunately, this lack of knowledge often blinds you to certain troublesome signs. If you would like to improve your overall understanding of your car, read on. This article will provide a helpful primer on one little-understood component: the CV joint.

The Basics

Unless you happen to own a car with back-wheel drive, your automobile is equipped with four constant velocity joints—or CV joints, for short. These joints are used to connect the front drive shafts to the vehicle's transmission. Two of the joints connect the outer sides of the drive shafts to your wheels while the other two connect the inner sides to the transmission.

The CV joints have a vital role to play in the proper functioning of your car: transferring the torque generated by your transmission to the wheels. They must be able to do this while simultaneously withstanding the up and down movements of the suspension. Furthermore, the CV joints are designed so as to allow the transfer of power even when the wheels are turning. In order to do this, a CV joint contains a number of internal metal balls, which grant it a full range of motion while still allowing it to accommodate the rotational force generated by the transmission.

Common Problems

CV joints, in themselves, are incredibly long-lasting components. In fact, it is perfectly possible for the original CV joints to remain working for the entire lifespan of a car. That's because the joint itself—as well as the grease used to lubricate it—is protected from exposure to environmental factors by a special piece of articulated plastic known as the CV boot. Of course, the CV joint can become damaged as the result of a collision.

Most CV joint problems, however, stem from damage to the CV boot. Cracks, tears, or other forms of boot damage allow water and dirt to penetrate into the joint. There they contaminate the grease used to lubricate the joint. This increases the friction to which the joint is exposed, thus accelerating the process of wear and tear. As the lubricant also leaks out through the cracked boot, corrosion will eventually set in, further hastening the demise of the CV joint.

Replacing an entire CV joint is a costly and time-consuming endeavor. Fortunately, by having your CV boots inspected on a regular basis, you can easily avoid this operation. If you're unsure about the state of your CV boots, ask your mechanic to take a look at them during your next tune-up.


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