What Is a Shock Absorber, And What Does It Work For?

What Is a Shock Absorber, And What Does It Work For?

A shock absorber is a part of the suspension system. It takes under control the vibrations caused by the wheel's up-down movement. Its function is often thought to provide comfort, but it is also a vital part for driving safety as well. This is very easy to understand or feel. When you remove the shock absorber from the suspension system, the oscillations that occur cannot be dampened. Then, the car will oscillate longer, and the connection of the wheel with the ground will weaken and sometimes even break. It means that you will not be able to keep the vehicle on track. If this happens when you are taking a bend, your vehicle will skid, or it will stop at a longer distance when you brake.

How Do Shock Absorbers Work?

A shock absorber produces a resistance force in the opposite direction of the movement that occurs when it lengthens or shortens. This force prevents continuous oscillation of the vehicle. To create that force, the shock absorber forces the oil inside it to relocate when it moves. As this flow passes through the valve groups inside, it encounters a resistance which makes the shock absorber to generate a force in the opposite direction against the movement. The shock absorber heats up while doing so and releases this heat from its body to the external environment. In other words, the shock absorber converts the kinetic energy generated by the wheel's movement and the potential energy stored on the spring into thermal energy and thus consumes the energy.

Symptoms of a Failing Shock Absorber 

There is simple testing equipment used at service shops to detect shock absorber failures. The equipment shakes the wheel to a certain degree and checks how long it takes to dampen this shake. At the same time, it measures the force the wheel applies to the ground with the load meters on it and determines how much the wheel's connection with the ground is weakened. If dampening takes long or the measured force falls outside the specified limits, it means that the shock absorber needs replacement.

In addition to that, there is also portable testing equipment. The equipment is placed close to the wheel you want to check before getting the vehicle pass over a bump at a low speed. The sensors on the equipment measure the oscillation. The shock absorber needs replacement if the oscillation takes longer than it is supposed to do.

Actually, you can also make a similar check. What you need to do is to quickly put your weight on an area of the vehicle close to the wheel, and to pull it back. If the resulting oscillation lasts longer than one and a half cycles, you should have your shock absorbers checked. Also, in normal use, if your car skids while cornering (front or rear wheels skid) or your vehicle dives (reduced front height and increased rear height), you had better take your car to a service shop.

Why Do Shock Absorbers Fail? 

Shock absorbers have a life span, like all car parts. However, their useful life may vary depending on the conditions of use. What is important here is to use the product specifically designed for your vehicle. Driving your car under the intended road and driving conditions is also another factor affecting the product's useful life. You might have seen the description "heavy-duty" in some car descriptions. This indicates that the product is designed for severe driving conditions. In addition to this, descriptions such as raised or lowered are important for selecting the right product.

Can Shock Absorbers Be Repaired?

Although very rare, some shock absorbers (these are mostly particular solutions produced in a limited quantity) can be designed to be disassembled so that their inner parts can be replaced. However, for vehicles used on highways, products are not designed to be disassembled. This is because the internal parts of shock absorbers are closed under a specific load and in very clean environments. If a shock absorber is opened by cutting, it cannot be used again. Cutting and re-welding the shock absorbers, especially the front ones (carrying the vehicle load), jeopardizes the drivers' life as well as the lives of those around him/her.