Symptoms of a Bad CV Axle and Its Bearings
CV Joint and Boot Replacement.
How to tell if I have a bad CV joint?
What Is a Drive Axle?
The drive axle is specifically an axle that is driven by the engine, and in most modern, front-wheel drive vehicles, the transmission and front axle are usually combined into a part called a transaxle. There can be some variation in the design for rear-wheel-drive cars, but for the most part, the assembly is similar. Split with differential and universal joints into two half axles, the drive axle connects to each wheel by way of a constant velocity joint, or CV-joint, to give the wheel assembly more free movement when making turns. Thus, a working drive axle is obviously crucial to your car's ability to drive.
A clicking noise when driving, especially when cornering, is typical of a drive axle that needs to be replaced. It can be difficult to hear, especially if you drive with loud music playing, but as soon as you're aware of it you need to check the wheel or have your car taken in to be looked at by a professional.
Vibration in the wheel when driving is another symptom of a bad drive axle. Fortunately, this symptom is more apparent than clicking. Noise and vibration when cornering can just indicate a problem in the CV joint, which is a cheaper problem to cure, but it still needs to be dealt with promptly in case there is a larger issue at hand. It is much better to be vigilant with repairs than assuming the problem is minor, since a malfunction with a drive axle while driving could be dangerous. Also, when the axle is in very bad condition it will feel as if you're driving a vehicle with a warped wheel.
With the vehicle jacked up and supported, move the drive axle up and down. There should be no excessive movement (no more than ½ inch or so). If you do feel movement, your drive axle is too worn and needs replacement as soon as possible. This is common especially when the vehicle has a great deal of mileage on the clock, typically more than 100,000 miles.
If you keep these three common symptoms in mind while driving, catching a drive axle problem early shouldn't be hard.
When a CV axle goes bad it must be replaced which usually takes about an hour to complete.