How often should shocks and struts be replaced?
Shocks and strut replacement is needed when any component within these assemblies breaks or is visibly worn. This usually occurs around 50,000 miles for shocks and around 80,000 miles for struts.
These are rough intervals and may change due to the quality of shock or strut installed, and the type of driving. Usually a good, easy test is to push down sharply on the car near the front or rear, then let go and see if the vehicle keeps bouncing. Good shocks and struts will absorb this bouncing energy and quickly level the car.
Second, shocks and struts should also be changed if there is visible oil leaking from the part or if any of the component is broken. Shocks are charged with oil, and use it to absorb energy created by hitting a pothole or crossing over uneven surfaces. Seals keep this oil in place, but over time they become dry and may become dislodged. Oil will seep past this seal and leak onto the exterior of the shock or strut. Overtime the components of a shock or strut may wear out and break. Usually the spring around the strut will break along the coil. Where the shock or strut mounts onto the chassis will wear, causing a rattling or clunking sound when driving over bumpy roads. The polished piston will rust over time and not allow the shock or strut to travel freely. All these conditions require replacement.
How do shocks and struts work?
Shocks and struts are designed differently, but perform the same basic function: keep the car firmly planted on the road. Absorbing the bounce makes the car easier to drive. Keeping the tires firmly planted on the ground allows for shorter braking distances. Shocks are the older design. They are primarily used in trucks and older rear wheel drive cars where space is ample. The shock absorber only absorbs or dampens the up and down motion created over uneven roadway. Instead of the car moving up and down. or the tires moving up and down, the initial motion is channelled through the oil and gas in the shock, which dampens the energy. Struts are a more modern adaption of the shock. They incorporate a coil spring into the design, which allows the strut to bear the weight of the car. Therefore, it must be bigger and stronger than a shock. This adaptation has allowed car manufacturers to eliminate other suspension components, and shrink the car’s weight and size while still providing a comfortable ride.
How do you know when to get your shocks and struts replaced?
A rattling or clunking sound, especially over bumps or uneven surfaces, is a sign that shocks and struts are worn. These components are mounted between the car’s chassis and suspension with rubber insulators or bushing surrounding one or several mounting bolts. As the rubber dries up and wears space is created where the shock or strut can move around and create noise. This noise is usually audible above 25 MPH to 30 MPH when shocks and struts are more active in the suspension of the car. A rise in the overall sloppiness of the car’s drivability is another symptom, although it may not be noticeable to a driver who unconsciously adjusts. The braking distance needed to stop the car will increase as shocks and struts wear. Sharp turns will be taken at lower speeds as they wear as well. If the car dips forward while braking or dips inward during a sharp turn, the shocks and struts are worn. A technician can provide advice on shocks and struts with a short test drive during routine service or oil change.
What can happen if shocks and struts are not replaced in a timely fashion?
Extended neglect of shocks and struts will lead to higher repair costs, and eventually will lead to an accident. Yikes! Worn shocks and struts will result in the premature wear of suspension and steering components. Ball joints, tie rods, and sway bar links amongst other components will carry more of the weight of the vehicle, so they will work harder to perform and wear out before normal expectancy. This wear is not only limited to suspension components, however, as tires will also take a beating. Tires will bounce more, developing strong wear patterns, especially along the inner edge of the tread. This choppiness can become so pronounced that an audible hum will be heard and a constant vibration will be felt. More important than worn suspension components, worn shocks and struts also make the car harder to stop and handle. With the tires not firm on the ground, the driver does not have complete control either in direction or in the adjustment of velocity. Turns are sloppy and braking is more difficult. Although most drivers adapt to this condition, a small lapse in attention to the road can lead to an accident.
What is the typical shock and strut replacement cost?
- Estimated part(s) cost = $25-$70 (each)
- Estimated labor cost = $200-500
Good news is, most automotive service professionals can perform this service. However, keep in mind, pricing will vary by location and your vehicle make and model. If you're not already, save time and use Openbay to compare pricing for shock and strut replacement from top auto repair shops in your area.
Service article written by an ASE Master Technician