Is a wheel bearing and an axle bearing the same thing?

Wheel bearings and axle shaft bearings serve similar functions. They each allow a wheel to rotate freely with minimal friction. However, whereas a wheel bearing is mounted in the wheel hub on a vehicle, an axle shaft bearing is installed inside the axle housing to support the outer end of the axle. In the case of a wheel bearing, its job is to allow the hub to spin. An axle bearing similarly allows the axle to spin.

What causes axle bearings to go bad?

Axle bearings can go bad for a variety of reasons. Lack of lubrication, contaminated lubrication from a lack of maintenance, abuse from harsh driving conditions, and excessive high mileage or wear are all factors that contribute to a bad axle shaft bearing.

What happens if a wheel bearing fails while driving?

If a wheel bearing fails while you are driving, the axle will leak gear oil. When that happens, brake failure is possible due to brake pad/shoe contamination. A failed axle shaft bearing can also cause the wheel to seize up and stop rotating. In severe cases, the wheel can even fall off of the vehicle.