Hub and Bearing

A hub and bearing cutaway.

The wheel hub and bearings take a tremendous amount of force as the vehicle travels down the road. It supports the vehicle's weight as it accelerates, decelerates, and corners. Many have a wheel speed sensor or its companion tone ring incorporated into their design. A damaged sensor or tone ring results in a corrupt signal and an amber ABS light.

The hub in the illustration has a sealed bearing installed. One part of the hub attaches to the spindle, and the other part attaches to the wheel; the wheel bearing spins between the two. A worn wheel bearing results in a grinding or growling sound that increases with vehicle speed.

A hub and bearing.

Striking a curb or pothole or excessive heat from the brake system or bearing can damage or warp the hub's flange. A warped hub causes a vibration that increases with vehicle speed.