Knowledge

Car shock absorbers – operation, failures, replacement

Shock absorbers are among the most heavily used components of a car. They have to cope with potholes, potholes, ruts and speed bumps, among other things. How do car shock absorbers work? Why is their condition so important and how to check whether they qualify for replacement? Here is our answer! 

What role do shock absorbers play?

The main task of car shock absorbers is to dampen vibrations and body lean caused by the deflection of springs. If coil or leaf springs alone were used without shock absorbers, the car would bounce like a rubber ball. Shock absorbers stabilise the body, ensuring a comfortable and safe journey for the occupants. The energy absorbed when damping unsprung mass is converted into heat.

However, this is not the only role of shock absorbers. An equally important function is to keep the wheels firmly pressed against the asphalt. Shock absorbers prevent the wheels from slipping off the road, which has a huge impact on driving safety. Even a slight loss of grip could result in the driver losing control of the vehicle. For this reason, shock absorbers have a huge impact on car handling, sudden manoeuvres and braking performance. To make sure that nothing surprises you while driving, it is worth choosing proven solutions, such as Magnum shock absorbers.

Signs of wear of shock absorbers

Wear of shock absorbers occurs gradually, so sometimes you can miss the moment when they lose their properties. Initial signs of wear include slightly poorer handling, suspension jerking at higher speeds and slightly more body roll. The differences can be subtle, so the untrained driver will not notice them and will get used to the deteriorated conditions.

Over time, however, worn shock absorbers will give more signs. These are, for example, strong rocking after passing a slowing threshold, characteristic “jumping” of the body during braking or frequent activation of the ABS or ESP system, even during gentle braking. Another symptom of the need to replace shock absorbers is uneven tyre wear. It is about worn squares and fraying, which indicate that the wheel jumps when braking.

What is the risk of driving with worn shock absorbers?

Driving a car with damaged shock absorbers is extremely dangerous. Worn shock absorbers drastically increase the risk of losing control of the steering wheel. They also increase braking distances, even when the car has new brakes and tyres. The driving comfort itself is not always lower, which can be deceptive. On the contrary, in some cases excessive body sway can be perceived as an improvement in comfort, especially in cars with relatively firm suspension.

Worn shock absorbers are also a danger to other suspension components. They accelerate the wear of tyres, metal-rubber parts and springs. They also have a negative effect on the operation of electronic systems that assist in braking and stabilising the vehicle, which is why it is so important to take proper care of this element of the car and to choose products of the highest quality, such as those found in the Magnum range.

Common failures of shock absorbers

The most common shock absorber failure is an oil leak visible to the naked eye. There is also often damage to the bearings and shock absorber connectors. These failures manifest themselves as rattling noises when driving or turning the steering wheel when stationary. In older cars, corrosion can be observed on the shock absorber components, which qualifies it for replacement. However, not all faults can be detected with the naked eye or by ear. The specialists at Magnum recommend that you regularly inspect and check the performance of your shock absorbers.

Shock absorber performance – when should they be replaced?

The condition of shock absorbers is checked during periodic technical inspection. Using special measuring equipment, the damping performance is tested and the results are given as a percentage. However, do not worry if the result is less than 100% – even new and fully operational shock absorbers do not achieve this value. A very good efficiency is approx. 70%, and only a value below 40% indicates a need for replacement.

A measurement may not be perfect. The results can be distorted by worn tyres, bushings or other suspension components. A measurement of the efficiency of shock absorbers in very light cars or cars with a simple suspension design may also give surprising results. In many cases, the instrumentation will indicate a much lower efficiency than is actually the case. For this reason, it is worth going to a professional garage, equipped with equipment taking into account the characteristics of the car model.

Replacing shock absorbers – what should you know?

You can replace shock absorbers by yourself, but this requires a large dose of technical expertise. Removing rusted and seized screws, which are often located in awkward places, can be problematic. A considerable risk, on the other hand, is connected with unscrewing a MacPherson strut. This requires the use of a special spring compressor, and the procedure itself is very dangerous. The experts at Magnum recommend that shock absorbers be replaced in a professional garage that is equipped with the necessary tools. This is all the more so because it is necessary to check and adjust the correct geometry of the car’s suspension after any interference with it.

The service life of shock absorbers is approximately 50-80,000 km, but much depends on the terrain in which the car is driven. It is therefore worth regularly checking the condition of the shock absorbers, if only by pressing firmly on the body above the individual wheels. The body should immediately return to its original position. If it makes a few bounces, it is time to change the shock absorbers. Note! Always replace both shock absorbers on one axle, even if the other is undamaged.

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