WHAT ARE SHOCKS?
What we call shock absorbers are really "dampers." The springs in a vehicle's suspension absorb bumps and other road shocks by compressing, and the shock absorbers control the amount of bouncing created when the springs rebound.
Several warning signs can tell you when shock absorbers need replacing, such as your car bottoms out over railroad tracks, speed bumps or dips in the road or keeps bouncing well after the fact. Other signs are unusual noises over bumps, excessive body lean in turns or that the front end of the car dives sharply in hard braking. Because shocks wear out gradually, you might get used to a looser, bouncier ride, much like you get used to longer stopping distances as brake pads wear out.
One way to test shocks is to push down hard on each corner of a vehicle. If the car continues to bounce after you let go, your shocks need replacing. However, this test may require quite a bit of strength, and with many high-riding SUVs and pickups it isn't easy to get the leverage you need.
Instead, you should have a qualified mechanic check your shock absorbers when your car is on a lift, such as when you have tires rotated. The mechanic will be able to see if there are major leaks (shock absorbers are filled with fluid), worn mounts or bushings, or physical damage such as dents.
Despite advice to replace shocks at specific intervals (often from those who sell replacements), such as every 80,500 kilometers, when you need to do it can vary by vehicle and how and where you drive. If you frequently drive over rough, pockmarked roads that put more stress on the shock absorbers, then you will probably need to replace them more often than if you drive mainly on smooth pavement. Carrying heavy loads also will wear out shocks faster.
LONGER STOPPING DISTANCE
Having worn shock absorbers on your vehicle can increase your stopping distance by up to 20%. As you increase your travelling speed this will also increase the distance it takes your vehicle to completely stop. This 20% extra distance can be enough to cause a fatal incident and should be attended to as soon as possible.
SWERVING & NOSE-DIVES
Does your car dip or swerve under braking? If so you need to have your shock absorbers checked. If you do dip or swerve under braking it decrease your control over the car which can be very dangerous in wet weather.
Are you getting vibrations through the steering wheel as you’re driving along? If your shocks are working properly they should keep your tyres in optimal contact with the road and there shouldn’t be any vibrations. If this problem occurs you need to be cautious, at high speeds the vibrations can be more intense and decreasing overall control of the vehicle.
CAR SLIDING & VEERING
Do you have to correct car sliding or veering across the road in mild winds? This is a tell-tale sign of worn shocks and can be easily fixed with a shock replacement.
ROCKING & RATTLING
If your vehicle rattles and rocks over bumps, railway tracks and uneven surfaces it is highly likely your shocks are heavily worn. Along with an unpleasant ride this rocking and rolling can be putting unwanted pressure on other car components and should be seen to as soon as possible.
UNEVEN TYRE WEAR
Can you see bald patches or uneven wear on your tyres? This usually means your tyres don’t have optimal contact with the road, which can be caused by worn shocks. This will have an affect on car control and tyre grip and both should be checked and replaced.