The Advantages of Shock Absorbers?

Shock absorbers help dampen the up-and-down movement of your car’s springs and suspension, providing comfort and good handling. They also make your vehicle less likely to bounce when you drive over rough road surfaces. Generally, shock absorbers are hydraulic (oil pump-like) devices that work to control the up-and-down movement of your suspension’s springs and other components that make contact with the road. It is for this reason that you should always check your vehicle’s shock absorbers with every service to ensure they are working properly and not overheating or failing.

In its simplest form, a shock absorber uses the principles of fluid mechanics to convert kinetic energy into thermal energy and dissipates it into the atmosphere. Using a combination of piston design, oil viscosity and other valving, the shock absorber creates resistance to the motion of your suspension that slows down its oscillations. This dampening effect is known as hysteresis, the natural tendency of materials to absorb and release a certain amount of energy in cycles when deformed under load.

Most cars have a basic shock absorber that consists of an internal oil-filled cylinder that contains a piston rod and a pressure tube with orifices (tiny holes). When the suspension moves up and down, the piston rod moves against the internal pressure tube, which is surrounded by a high-pressure charge of hydraulic fluid. As the piston moves up and down, the orifices allow small amounts of fluid through at a time, which is slowly released to slow down the piston’s movement.

The speed of the piston’s movement is a function of its size and valving, which is designed to provide the right balance between ride quality and stability. A sluggish piston can create a harsh or bouncy ride, while too much rapid movement results in unstable handling and the potential for premature shock wear and damage.

Different shock absorbers are used for light-duty, medium-duty and heavy-duty trucks and SUVs, as well as full-sized vans. This is because these vehicles have larger unsprung mass—the weight of the axles, wheels and tires, as opposed to the sprung mass—which requires a greater degree of dampening to reduce hysteresis and other vibrations.

In addition, these vehicles often have suspension travel that is longer than a passenger vehicle, and some shock absorbers may be pushed to their limits in this application. When they are overloaded or not valving-matched to the vehicle, shock absorbers can fail by compressing too far and punching through their mounting points or extending too long and damaging their internal valves and structures. There are simple tests for this that can be performed in many automotive service shops, such as shaking the vehicle and measuring how long it takes for the shake to be dampened. This is a good indication of how worn or damaged the shock absorbers are, and that they need to be replaced. Shock absorber failure is a common cause for wheel-spin and erratic handling. Adding a shock absorber kit or replacing your vehicle’s stock shock absorbers can restore the proper ride and handling to your truck or SUV and keep it safer and more comfortable for you, your family and passengers.