What Are Struts & Shocks?

by Contributing Writer

Struts and shocks are on your vehicle to limit how far the suspension can travel. When struts and shocks are working properly, a vehicle will not bounce continually, even when on an uneven road. This is achieved by taking the movement of the springs and changing them into heat-based energy. The hydraulic fluid in the shocks or struts causes this heat energy to dissipate.

Shock Suspensions and Strut Suspensions

A strut holds the spring in place in a strut-based suspension. The vehicle is structurally supported by it. Struts are most common type of suspension in cars. Shocks are mounted directly onto the frame of the vehicle on one end, and on the other end they are attached to the vehicle's suspension. Shocks do not improve upon the structural support for the vehicle because they do not support it. Shocks are used on cars occasionally but are most common on SUVs, trucks and vans.

Problems With Brakes

Worn struts and shocks can cause several problems on a vehicle. The first is extended braking distance. This is because the the weight transfer between the body of the car and the suspension is no longer as smooth as it once was. This causes more pressure than necessary on the brakes of the vehicle. The added stress on the brakes causes them to take longer to stop the vehicle.

Problems With Steering

When shocks and struts are worn, they also have an adverse effect on the steering in a vehicle. They can cause the vehicle to be unable to control the roll of its body when turning, and this reduces the grip of the tires on the road. The steering system will have a longer reaction time and make it more difficult for the driver to steer the car.

Problems With Stability

When a wheel is connected to a shock or strut that is worn, it tends to bounce and shift excessively while the vehicle is in motion. This gives the driver of the vehicle less traction to work with. The excessive bouncing and shifting can cause other parts of a vehicle to wear out more quickly, such as the tires and the other parts of the suspension.

Signs Of Wear

There are ways to test check whether the shocks and struts on a vehicle need to be replaced. If the vehicle is bouncing very excessively (more than three times when crossing an intersection or a dip in the road) it may be time to have your shocks and struts inspected. Another telltale sign is a vehicle that rocks back and forth multiple times when stopping. If the vehicle tends to drift to the left or the right while going straight on a road, the shocks and struts may be worn down. When changing lanes, the vehicle may also sway from side to side instead of staying stable. You can notice this easily as you enter a freeway ramp, because the vehicle will lean excessively, making it seem partially disconnected from the road.

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