If you've been hearing a clicking or grinding sound when turning or cornering lately, then you might want to take a look at the axle where the sound is coming from. You can either get under the car or lift it up, then grab the axle and try to move it back and forth. Any amount of play greater than ½-inch and you might have a bad CV axle. Another indication of a bad axle could also be an unordinary amount of vibration (especially when coupled with a clicking sound); however getting your CV joint race and bearings re-packed may fix the problem. This is typically caused by a ripped or torn CV boot that is allowing road debris into the joint causing increased wear. Many times, CV axle failure is much more serious, and could result in a loss of control of your vehicle if gone untreated. Reasons for this kind of failure usually point to some collision or physical damage to the CV axle, and should not be taken lightly.
An axle is the center shaft around which a wheel spins. Axles have been around as long as wheeled forms of transportation have, and as the demands of vehicle operators have grown so has axle technology. From carts and carriages to cars and trucks, suspensions and axles have evolved together to improve drivability and comfort while maintaining functionality. The Rzeppa type CV axle was born out of the necessity to add independent suspension to the drive wheels. It does this by expanding on the design of a simple Cardan style universal joint, by using a race or gait of ball bearings that rotate forward, backward, and around a large grooved sphere that's attached to the axle shaft. If the race is built into a joint that's attached to the transmission, it will rotate along a fixed axis. The axle shaft, however, may rise and fall as the suspension adapts to road conditions. As that happens, the grooved sphere remains centered inside the joint as it rotates and the ball bearings packed in the race continue to move through the grooves normally. The CV axle was a marvelous invention back in the 1920's that we now take for granted today.
Changing your damaged CV axle doesn't have to be an all-day affair. An experienced mechanic can remove and re-install a CV axle in about an hour or two with the right tools. Remember, above all else, observe safety precautions while you attempt to perform any work on your car.