Bushings are cushions made of rubber, polyurethane (often shortened to “poly” or “urethane”) or other materials. They’re mounted on car suspension and steering joints to absorb road bumps, control the amount of movement in the joints and reduce noise and vibration. Bushings often take the form of fat, rubbery washers through which suspension components — or the bolts that attach them — pass.

When bushings wear, they allow more movement. The driver may feel a shimmy from the front of the vehicle, or hear clunking or rattling noises on rough roads, when turning the wheel or in hard braking. Drivers may also experience poor handling or loose steering. Failure of rear suspension bushings may be harder to detect as they don’t involve the steering system and may be less affected by cornering.

Bushings are used for control arms, stabilizer bars (also called sway bars), ball joints, tie rods, shock absorber and strut mounts, and other suspension and steering parts, as well as in engine and transmission mounts. They wear and crack from friction, age, heat, exposure to road salt and lubricants, and the stress of frequent movement and weight loads.

Like the cartilage that protects knees and elbows, when bushings wear, it puts more stress on the joints and connected parts. Like bone-on-bone contact, worn bushings can allow metal-on-metal contact. Worn control-arm bushings can allow the vehicle’s front end to slip out of alignment and cause premature tire wear.

What feels or sounds like worn shocks or ball joints, or another suspension problem, may not be the fault of the part itself but the bushing that cushions joints and mounting points. A thorough suspension bushing inspection should reveal which is the culprit. For example, a loose stabilizer bar will allow more body lean (and perhaps noise) in turns, but if the bar isn’t bent or broken, maybe only the bushings need replacement.

On the other hand, repair shops may recommend replacing the part and not just the bushings, because if the are worn, it may indicate the part itself is old and may not last much longer. In addition, many bushings are pressed into a metal sleeve and difficult to remove, which increases labor time and costs. On some cars, control-arm bushings cannot be replaced separately, so the mechanic may have to replace the control arm itself.

A bushing is one classification of the overall category of bearings. A bushing is a thin tube or sleeve that allows relative motion by sliding (our type), as compared to rolling. A bushing might also be called a sleeve bearing. However, the term sleeve bushing would be redundant. Thus, a bushing is a bearing, but a bearing is not necessarily a bushing type.

A bearing is the general term for something that allows relative motion between two components, surfaces, etc.

Because of the amount of labor associated with installing new bushings on some vehicles, the overall cost can be high relative to the bushings themselves. New bushings, though, can markedly improve the ride and handling of a vehicle that’s been in use for several years.

If you feel like your suspension system needs repair, please bring your vehicle into any one of our three locations of Sierra Car Care and Tire Centers in the Reno area and one of our ASE Certified Technicians will take care of you.