Axle shafts, or CV (constant velocity) shafts, are essentially long metal poles that connect the wheels of your car to the transmission gears, and allows the wheels to rotate. The transmission works to rotate the axle shafts, which in turn causes the wheels to rotate. If the axle shaft is damaged, you are quite simply not going to be going anywhere, because your car’s wheels will not turn.
Axle / CV shaft assemblies do not really have a “best before” date. Most of the time, they will last the life of your vehicle. However, having said that, keep in mind that whenever your car is in motion, your axle / CV shaft assembly is working. And, like all moving metal parts, the axle / CV shaft can be subject to wear. It needs to be properly greased in order to prevent wear, and leaking grease is the most common reason for the assembly to fail and need to be replaced. Axle shafts consist of the shaft itself as well as CV joints, and “boots,” which are containers that hold the axle grease. If the grease leaks out of the boots, the joints lose lubrication, dirt gets in, and the axle can wear out.
Signs that your axle / CV shaft assembly may need to be replaced include:
- Grease around the tires
- Clicking noise when turning
- Vibration when driving
Any problem with your axle / CV shaft assembly is a serious safety issue. If you notice any of the above symptoms, you should consult a professional mechanic without delay and have the axle / CV shaft replaced immediately.
This article originally appeared on YourMechanic.com as How Long Does an Axle / CV Shaft Assembly Last? and was authored by Valerie Johnston.