When Do You Replace Shocks?
Most mechanics recommend changing your car's shock absorbers every 60,000 miles. However, you should also test about once a year or ever...
Most mechanics recommend changing your car's shock absorbers every 60,000 miles. However, you should also test about once a year or every 12,000 miles. While testing the shocks can be a relatively simple and safe procedure, changing them should only be done by an expert. The replacement procedure depends on if the shocks are contained within assemblies with coil springs or not. Even then, the exact procedure always varies for each model vehicle.
Testing the Shocks
Start with your tires and see if they are worn down abnormally, especially at one end. See if the oil or gas within the shock absorber is leaking and if there is any corrosion or worn bushings. See if the coil springs have snapped and if the vehicle's level is lower at one end than the other. Measure the gap between the wheel and wheel arch and then bounce the vehicle by pushing down at the end. See if it immediately bounces back up to the original high point or settles down lower.
Changing Shock Assemblies
Raise and support the vehicle's front or rear end on jack stands and remove the wheels; loosening the lug nuts before raising the vehicle makes the wheels easier to remove. The shock assembly is mounted to the top of the wheel well with the bolts accessible from the engine compartment or trunk. Some components in the engine like the battery or air filter housing might need removing to reach the bolts and remove them. Go under the vehicle and remove all other bolts on the assembly, which is usually connected to the stabilizer bar and control arm. You need to support the control arm with a floor jack before disconnecting it. You might also need an assistant to remove the assembly given its weight. Use a heavy-duty spring compressor to compress the coil spring and then unscrew the nut on top of the absorber. Install the new shock absorber in the module and tighten the nut to the correct torque. Be very careful when releasing the spring compressor. Install the shock assembly in reverse order of removal.
Changing Shock Absorbers Alone
When the rear shocks aren't within coil assemblies, you can reach them without removing the wheels on some vehicles, but you still must raise the rear end with jack stands. Also, raise the differential with a floor jack so there is no weight on the shocks. Remove the bolt connecting the shock absorber to the axle or steering knuckle first, then remove the other mounting nuts. If you need to compress the shock to remove it and install the new one, be advised that this will take a lot of force.
