Coilovers vs. Struts: What’s the Difference?

Typical suspension maintenance involves replacing shock absorbers or struts and sometimes coil springs. On the other hand, upgrading might involve new springs and shocks or struts or maybe coilovers. So, how do you choose one over the others? Whether part of a lift kit, suspension drop or suspension upgrade, coilovers and struts are two related but slightly different parts.

What Are Coilovers vs. Struts?

There are two general stock configurations of coil springs and shock absorbers. In some cars, the coil spring is located apart from the shock absorber, supporting the vehicle on its own. The shock is mounted separately from the spring.

In other configurations, the coil spring is mounted to the shock absorber as a single unit supporting the vehicle. This is typically referred to as a strut but is sometimes called a coilover. In fact, coilover is just a shortened version of “coil spring over shock absorber,” and sometimes coilovers are indeed struts but not always. In the field, the main difference between coilovers vs. struts is adjustability and customization.

Coilover Customization

Typically, original equipment manufacturer replacement struts or coilovers come with no options. That is, one cannot choose shock absorbers’ damping rates, spring rates or ride height. Of course, in the aftermarket, there are many suspension upgrade options. Coilover kits don’t include all options, but you can choose which ones work best, depending on how you plan to drive your vehicle. These are some of the factors to consider:

• Overall Length: Coilovers are available in different lengths, which affect the ride height of your vehicle. For a sporty ride, a shorter coilover will lower the vehicle’s center of gravity, reducing the chance of a rollover when driving around corners. For off-roading, longer coilovers give you better ground clearance and creates space for larger tires.
• Spring Rates: Higher spring rates give you a stiffer ride, while lower spring rates deliver a softer ride. Variable-rate springs stiffen as they compress, unlike linear-rate springs.
• Damping Rates: Some shock absorbers allow you to adjust their shock absorption and rebound to your preference. This is usually done via knobs at the top and bottom of the shock.
• Ride Height: This may be adjustable by threading the shock absorber into its base. Otherwise, ride height is set by adjusting the spring preload.
• Spring Preload: Adjustable locking rings compress the spring partially, which determines ride stiffness and may affect ride height, depending on coilover configuration.
• Remote Reservoir: For off-road applications, coilovers equipped with a remote reservoir improves cooling to prevent shock fade.

For vehicles equipped with adaptive suspension, look for coilovers with the appropriate electronics. This should prevent warning lights from coming on after you’ve upgraded your suspension.

Who Uses Coilovers vs. Struts?

Whether you use coilovers vs. struts depends entirely on your preferences and how you use your vehicle. To retain stock ride height and ride quality, original manufacturer struts are a no-brainer and require no additional adjustments after installation. On the other hand, lifting or lowering coilovers is an easy upgrade for any home mechanic. Just a few hours and some basic tools can drastically improve the quality of your ride.

Keep in mind that lifting or lowering your suspension usually changes alignment angles, which can lead to abnormal tire wear. If you do this, get a suspension alignment as soon as possible.

Check out all the shocks and struts available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on coilovers vs. struts, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

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