What are shock absorbers?
In an ideal world, all road surfaces would be even and smooth, allowing you to drive freely without worrying about your tyres or suspension system. Unfortunately, bumps, potholes, and rough roads are an everyday reality for drivers. Thankfully, modern vehicles have efficient damping systems which reduce the vibrations and unwanted movements caused by driving on uneven surfaces. The shock absorbers play a key role in this.
Shock absorbers, also known as suspension dampers or “shocks”, are devices that balance the compression and rebound movements of the suspension springs. They also cushion the body components from shocks and reduce the intensity of vibrations. They do all this by converting kinetic energy into thermal energy. For example, when a car goes over a bump, the springs react and absorb the kinetic energy. To stabilise the movement of the car, this energy must then be dissipated. A piston is actuated in the shock absorber cylinder, pushing out the oil inside. This oil has to be forced through small openings or absorber valves, creating resistance. In turn, the resistance slows down the piston and suspension movement while generating heat.
These components are essential for maintaining road contact, vehicle stability, and control. If your shock absorbers aren’t working properly, you may notice that the vehicle bounces uncontrollably and swerves when turning. It will also negatively affect the vehicle’s braking efficiency.
Types of shock absorbers
Nowadays, the most common suspension dampers are hydraulic, however, there are many different kinds of hydraulic devices with varying designs and components. Here are three popular types of dampers that are used in modern vehicles:
How long should they last?
As a general rule, you can expect your shock absorbers to last for at least 4 to 5 years unless they are subjected to extreme driving conditions. The replacement interval will largely depend on the driver’s habits, type of vehicle (e.g. light or heavy-duty), condition of the roads and vehicle’s mileage. Off-roading, carrying heavy loads or frequently driving over potholes and rough surfaces will cause the components to wear out faster. It is advisable to inspect them annually or at least once every 50,000 miles.
It is important to replace them when they are faulty for your own safety and the safety of the passengers. If you don’t you could lose control of your vehicle the next time you encounter a bump in the road or pothole.