Rear axle bearings support the outer ends of your rear-wheel-drive vehicle's axles. These bearings, one per side, will start to make noise when they begin to fail.

If not changed in a timely fashion, they can cause serious damage, resulting in axle shaft replacement and maybe even the axle housing itself

The main reasons that a wheel bearing fails are: Impact damage or poor road quality – all impacts from driving through a pothole, driving over speed bumps or hitting the curbstone can damage a wheel bearing and reduce its lifespan. Poor quality wheel bearing – a wheel bearing is continuously under enormous pressure.