The axle assembly is used in front-wheel drive and all-wheel drive vehicles. It connects on one side to the transmission and to the wheels via the CV joint. Its job is to transfer torque from the transmission to the wheels and connects the two front wheels of the vehicle, allowing them to move and rotate freely. Sometimes the axle assembly also allows the wheels to move independently of each other. As a bare minimum a basic axle assembly will comprise of an axle, axle housing and bearings. Some however, are more complex and include the suspension and steering systems.
Damage to the axle assembly tends to be more common in off-road vehicles and may be indicated by a grinding noise when changing gears. It’s also worth noting that the axle assembly can be damaged if its connecting CV joint is worn. To keep the joint in good condition, it’s important to ensure that the protective rubber CV boot isn’t damaged. This contains grease which lubricates the CV joint. If it becomes damaged, this grease can become contaminated with grit and cause friction to the joint.