Bushing (isolator)

A bushing, or rubber bushing, is a type of vibration isolator. It sits between two parts and dampens the energy passing through it. A common use is in vehicle suspension, where a bushing of rubber, synthetic rubber or polyurethane separates two metal faces while still letting them move, so the suspension can travel freely over a bump and little noise or vibration reaches the chassis. Bushings often take the form of an annular cylinder of flexible material inside a metal casing or outer tube, and some have an internal crush tube. Unlike a plain bearing, the motion between the two parts is taken up by strain in the rubber rather than by shear or friction at the interface.