A CV joint is a short form for a constant velocity joint. These joints make sure you have a smooth ride free from knocking.
Car lovers like to take care of their cars and know exactly when which part needs replacement. With a CV joint there are only a few determinant factors that can lead you into getting a replacement. These in most cases just wear out. There is no such a thing as a total breakdown for an ATV CV joint, so you have ample time to find another one while your car is still running. Two things are really bad here, one is bad grease and another one is loss of lubrication. These are symptoms that point out to the failure of your joint. When you are driving and on a turn you hear a clicking sound it means your CV joint is worn out. The way to check this out while driving is to put your car in reverse and drive backwards in a circle. If the sound seems louder it means you will have to buy another one and replace it with the damaged one soon as possible.The ones in the front end can be seen by tilting the wheels.
Cars make various sounds and if you can distinguish one from another you can tell exactly what the problem is. For example, when you feel a vibration while driving it means your inboard plunge joints are not working properly. Your axles may also be responsible for such a vibrating sound. If the vibration increases with speed it means that either one of your tires is not balanced properly.
If you have a front wheel drive, it is a good idea to check the boots near the CV joint for cracks, tears and punctures. Also check for loose or missing clamps and fix the problem soon as possible. It is not a good idea to go around driving with a damaged boot as this will surely damage your joint.