Shocks and Struts Maintenance

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Shocks & Struts – The Basics

Many drivers know that shocks and struts are important to their car, but they don't always understand what shocks and struts do for them.

The primary purpose of a shock is to hold tires to the vehicle’s tires to the road. We call this "ride control". A vehicle’s springs support the weight of the vehicle, but the shocks dissipate the energy of road irregularities – like potholes and expansion strips – so your smooth, safe ride is not disrupted.

But shocks aren’t just for comfort. When you hit your brakes suddenly or need to turn abruptly, your shocks control the rolling and pitching of your vehicle’s body. Since they affect steering, road handling and braking, shocks are very important for safety, and especially important in emergency maneuvers.

Today’s vehicles often have struts instead of shocks. Struts are compact assemblies that allow vehicles to be lighter and have more interior room. Like a conventional shock, they control the up and down movement of the tire. But they are engineered to control the rotation of the suspension during steering as well. While a shock is non-load bearing, struts are a structural load-bearing component of a vehicle’s suspension system.

Safety

Driving with worn shocks and struts is as risky as driving on bald tires or using brakes that are past their prime. Under hard braking, tire contact with the road is critical, so driving with worn shocks or struts can have a significant effect on braking distance. Shocks and struts also play an important part in maximizing the life of other steering and suspension components by minimizing excessive movement.

Ride control degrades over time so changes in the quality of your ride may not be immediately noticed. Therefore, tire wear is an important indicator of ride control. Uneven tread wear, or tread cupping, which is regularly-spaced wear around the tire, are often a result of degraded shocks or struts.

After 50,000 miles, you should have your shocks inspected whenever your brakes are inspected. A good rule of thumb is to have your shocks inspected once a year or every 12,000 miles.

Warning Signs

Look for these signs that your shocks or struts may be deteriorated. If you experience any of these signs you should have your ride control inspected immediately.

• Vehicle Ride is Harsh, Bumpy or Shaky
• Uneven Tire Wear
• Vehicle Nosedives When Braking
• Vehicle Veers in Side Winds
• Vehicle Bounces After Hitting a Bump
• Dented or Damaged Housing
• Leaking Fluid from the Shock Housing
• Vehicle Sways or Leans in Turns
• Self-Inspection

You may have also heard about the "bounce test" as a means of self-inspection. To perform a bounce test, push your bumper as low to the pavement as possible and let go. A car with healthy shocks should settle into place quickly. If the car "bounces" up and down more than twice before settling back into place, it may have worn shocks.

Again, it is important to note that no self-inspection or individual symptom can take the place of a thorough ride control inspection by a qualified professional.

Do-It-Yourself or Do-It-For-Me?

While shock replacements are typically a light to medium DIY job, strut replacements are more complicated and require special tools and equipment, such as a spring compressor. If you determine that your struts need to be replaced, consider using a fully-loaded strut assembly that comes pre-assembled with a strut, strut mount, and spring, and includes all of the components required for a complete strut replacement for your specific application. A fully loaded strut assembly converts a heavy DIY job into a job a medium DIY job requiring no special tools.

If you decide to have someone replace your shocks or struts for you, we always recommend that you choose a qualified professional who will help you choose the ride control products that are right for your needs.

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