Rubber Bushings

Every car has bushings, usually made of rubber or of material that contains rubber. They are used to cushion areas where the body connects to the frame as well as to provide cushion and movement in areas that require a range of motion such as on the steering knuckle.

Bushings are located on the suspension, steering, engine, transmission, and other locations where moving parts meet the body of the vehicle. Their job is to absorb most of the shock and vibration so that it doesn't get transmitted into the passenger compartment of the vehicle as well as to protect those components from reverberations and shock from other components.

Most bushings are named for the function they serve. So motor mounts are the bushings between the engine and the car's body and frame. Leaf spring bushings are on the leaf springs (suspension component), etc.

Often, bushings are also designated by their durometer index or rigidity, a measurement of the amount of force that the bushing returns (does not absorb). The higher the durometer number, the less flexible the bushing is.

Like any other component on your car, bushings can eventually wear out. Unlike other components, however, they actually receive less wear and tear the more often they're used. Because movement and friction causes the rubber to become more viscous and less brittle, using your vehicle often actually preserves the bushings.

Eventually, however, they will require replacement. When the vehicle begins to get "rackety" making noise while driven or when cornering or riding over bumps, it's likely that bushings in steering, suspension, or body connections are going bad or have broken apart.

Most mechanics will check the bushings on older cars whenever they are underneath the vehicle for routine maintenance (oil, filter, etc.) and should alert you if they require changing. Many of your vehicle's bushings will be visible if you look for them, so you can also check for cracks or breaks yourself.

If bushings go completely out, they should be replaced quickly because without bushings, there will be metal-on-metal contact that is not supposed to be happening, leading to worse problems down the road.

Check your vehicle's owner's manual for the location of rubber bushings on your car.

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