Should You Replace Struts When You Replace Shocks?

Many auto repair shops and mechanics recommend replacing a car's struts and shocks at the same time. There is some sound reasoning behind that approach as both components can affect a car's handling, safety, and ride quality.

It's important to keep in mind that when one wears out, the other probably isn't far behind. However, only one of the two is showing signs of wear, it's acceptable to replace shocks and struts at different times.

While some people use the two terms interchangeably, there is a difference between shocks and struts. Shocks, or shock absorbers, use fluid transfer within a cylinder to control the movement of a vehicle's suspension. Without the shock a car might bounce down the road similar to a pogo stick. In addition to controlling bounce, shocks help with roll and sway when cornering, diving during braking, and squatting under acceleration.

Struts incorporate the same control mechanism as shocks, but add a structural component to the car's suspension. Vehicles without struts employ upper and lower control arms that attach to the spindle or hub via ball joints. Struts replace the upper control arm and upper ball joint, making the system more compact and reducing weight.

Some cars don't have struts at all, and others don't have shocks, except for the shock-absorbing feature incorporated into struts. Many modern cars employ a combined approach with struts in the front (or rear) and shocks controlling suspension movement at the other end. Whatever the setup, they'll have shock or strut pairs front and rear. Unless there are extenuating circumstances, such as a damaged component, it's recommended to change shocks or struts as front or rear pairs.

Many DIY mechanics will possess the necessary wrenching skills to change the shocks on a car without having to pay someone else. Changing struts is more complex, and requires a trip to an alignment shop anyway, so it's worth getting a repair quote before tearing your car apart.

Some struts contain replaceable cartridges that allow them to be refurbished without the need for replacing the entire component. While this feature could save you some money when your struts wear out, replacing strut cartridges is not typically recommended as a DIY project without specialized knowledge.