Suspension Parts > Suspension Strut

Car strut: important components for a comfortable and safe ride

Car struts are one of the most important components in a vehicle's suspension system, ensuring a comfortable and stable driving experience. These common but often underestimated parts play a key role in a car's handling and ride comfort. The function of struts is to absorb shocks caused by road irregularities, reduce bump vibrations and keep the car's body balanced to prevent discomfort and ensure vehicle stability. In this article, we will introduce what shock absorbers are, how they work, the different types and how to maintain them to ensure the optimal operation of the vehicle's suspension system.

struts are in this category (shock absorbers are in another category)

The parts of a car's suspension system, the shock absorber and the spring shock absorber, differ in their construction and function. Here are their main differences:

 

1. spring shock absorber (strut in English)

Description: A coilover shock absorber combines a shock absorber and a spring into one unit. It is often also called a strut (e.g. MacPherson strut).

features:

acts as a shock absorber, dampening movement and vibrations.
carries the weight of the vehicle and helps maintain suspension geometry and wheel alignment.

placement: often used in front axle suspension, but can also be found on the rear axle.

Construction: the spring is mounted around the shock absorber, forming one compact unit, which simplifies the suspension construction.

Example: common on modern vehicles, especially with MacPherson strut suspension.

2. shock absorber

Description: A shock absorber is a component whose main function is to dampen suspension movement and prevent excessive swaying of the vehicle.

function: controls the movement of the suspension and spring, reducing vibrations and keeping the tires in close contact with the road surface.

arrangement: work with separately mounted springs (springs carry the weight of the car).

construction: only a damping element that does not bear the weight of the vehicle or have any load-bearing capacity.

example: common on vehicles with independent suspension systems where the spring and shock absorber are separate components (e.g. multi-link rear suspension).

1 and 2 spring shock absorbers (strut)
3 and 4 shock absorbers (shock absorber)

main differences:

characteristic	shock absorber	spring shock absorber (strut)
construction complexity	only the damping component	combines spring and shock absorber
carrying capacity	does not support the weight of the vehicle	bears part of the vehicle's weight
arrangement	work together with separate springs	spring and shock absorber are combined in one system
place of use	rear axle, complex suspensions	mainly on the front axle, in simplified suspension
maintenance and replacement	easier and cheaper	more difficult and expensive to replace

 

summary:

• A shock absorber is a simple damping device that works in conjunction with a separate spring. It is not a load-bearing part.
• A coil spring is an integrated system that performs the functions of both a shock absorber and a spring and supports the weight of the vehicle.

The correct choice depends on the vehicle's suspension type and manufacturer's design.

How does shock absorber work?
The working principle of shock absorbers is based on a combination of two main movements – compression and recovery. When the car’s wheels come into contact with the ground and the kinetic energy increases (for example, when driving over a hill or a pothole), the shock absorber compresses and absorbs some of this energy. The shock absorber then begins to recover, returning the energy and bringing the car back into balance.

Inside the shock absorbers is a liquid or gas (such as nitrogen) that helps control the movement and converts the kinetic energy into heat. This heat is dissipated into channels inside the shock absorber, which help prevent overheating and ensure smoother operation.


shock absorber parts:

1. strut mount (bearing plate)

function:

The shock absorber support bearing is a part that connects the shock absorber to the vehicle body. It allows the shock absorber to rotate in accordance with the movement of the steering wheel (on the front wheels) and ensures a stable connection between the suspension and the body.

• Front strut mounts often contain ball bearings that allow the shock absorber to pivot.
• Rear support bearings are simpler because they don't have to rotate.

problems:

Worn out support bearings can cause unpleasant noises, loose suspension, and affect vehicle handling.

2. spring

function:

The spring is the component responsible for the elasticity of the suspension. It keeps the vehicle at the correct height, absorbs impact energy from the road surface and distributes the load evenly. The spring works together with the shock absorber to ensure a stable and smooth ride.

• The springs are made of strong steel and designed in a spiral shape.
• Springs also determine the stiffness and load-bearing capacity of a car's suspension.

problems:

Over time, springs can wear, rust, or break, causing the vehicle to lean or the suspension to become less stiff.

3. shock absorber

function:

A shock absorber is a device that controls the movement of a spring, dampening its vibrations and impacts. It provides stability to the vehicle and helps keep the wheels in contact with the road surface.

• Shock absorbers usually operate on a hydraulic or gas-fluid basis to dissipate impact energy.
• In the case of McPherson-type suspension, the shock absorber also includes the spring and support bearing mount.

problems:

Worn shock absorbers cause poor handling, increased braking distances and an uncomfortable ride. Typical symptoms are excessive vibrations after potholes or noises from the suspension.

4. dust shield

function:

A protective rubber is a part of a shock absorber that protects its moving parts from dirt, dust, water, and other harmful elements.

• The protective rubber extends the life of the shock absorber and its seals by preventing dirt from entering the interior of the shock absorber.
• It works in close cooperation with the impact limiter, which prevents the shock absorber from being compressed too deeply.

problems:

A torn or worn protective rubber leaves the shock absorber unprotected, which can cause it to wear out quickly or even fail.

shock absorber parts:

1. nut - nut
2. strut mount (bearing plate)
3. upper spring seat
4. dust shield
5. strut shaft
6. lower spring seat
7. strut body

                    














The importance of shock absorbers in vehicle performance

• Ride comfort: shock absorbers reduce the impact of road irregularities, ensuring a smooth and comfortable ride. Without functioning shock absorbers, the ride would become uncomfortable as the car would constantly jump and shake.
• Vehicle stability: The function of shock absorbers is to keep the car's body balanced and prevent excessive body movement, especially when cornering, braking, or driving on uneven terrain. Without proper shock absorbers, the car can become unstable and lose control, which can be dangerous.
• Tire wear and suspension health: Shock absorbers help keep the tires in constant contact with the ground, which reduces uneven tire wear. They also protect other suspension components from excessive wear, extending the life of the entire suspension system.
• Safety: Shock absorbers help maintain the vehicle's balance and reduce the tendency to lose traction, especially in emergency situations or bad weather. They are essential for ensuring the stability and safety of the vehicle.

different types of shock absorbers
Modern vehicles use different types of shock absorbers, depending on the needs of the vehicle and driving conditions. The most common types of shock absorbers are:

• monotube shock absorbers:

Description: Monotube shock absorbers contain a single ring that houses both the piston and the fluid. They are designed to provide better cooling and stronger performance, especially in sports cars and heavy trucks.
Benefits: for better cooling and smoother operation, especially in extreme driving conditions.
Application: sports cars, off-road vehicles and heavy trucks.

• twin-tube shock absorbers:

Description: Twin-tube shock absorbers have two rings: an inner ring where the piston is located, and an outer ring that contains a liquid or gas reservoir.
Advantages: They are more affordable and provide a comfortable driving experience, being suitable for normal everyday driving.
Application: most everyday cars and minivans.

• gas-filled shock absorbers:

Description: These shock absorbers contain pressurized gas (e.g. nitrogen) which helps prevent foaming of the fluid and ensures smoother operation.
Benefits: reduces fluid foaming, improves performance and stabilizes the vehicle.
Application: often used in sports cars, off-road vehicles and cars that require better dynamics.

• adjustable shock absorbers:

Description: These shock absorbers allow the driver to change the stiffness of the suspension according to driving conditions.
Advantages: flexibility and adaptability to different driving conditions, providing a sporty driving experience or a more comfortable ride.
Application: used in sports cars and luxury cars where there is a desire to customize the vehicle's behavior.

• air shock absorbers (air shock):

Description: Air shock absorbers use pressurized air instead of fluid to provide additional adjustability and vehicle height control.
Advantages: Adjustable vehicle height, which is well suited for trucks and vehicles that carry heavy loads or create higher suspension loads.
Application: SUVs, trucks and vehicles that must withstand heavy loads.

signs that shock absorbers need replacing

Over time, shock absorbers, like all other parts of a car, wear out. The following signs indicate that shock absorbers need to be replaced:

• Excessive bouncing or swaying: If the car bounces or sways excessively after driving over potholes, this may indicate worn shock absorbers.
• Signs of fluid leakage: If you see fluid leaking from the shock absorbers, this is a clear sign that the seals are damaged and the shock absorber is no longer working effectively.
• Uneven tire wear: If your tires are wearing unevenly, it could be a sign of a problem with your shock absorbers, as they are unable to keep the tires in constant contact with the ground.
• Impaired handling and stability: If you feel that the car is difficult to steer or the car is less stable when cornering, the cause may be worn shock absorbers.
• Increased braking distance: If the car needs more space to brake or the brakes feel less responsive, the shock absorbers may be faulty, as they affect the entire suspension system.

shock absorber maintenance

To keep shock absorbers in good working condition, it is important to maintain them regularly:

Check regularly: Have your car's shock absorbers checked regularly, especially if you feel that the vehicle's behavior has changed.
Avoid rough driving: excessive travel over potholes or heavy loads can accelerate shock absorber wear.
Check for leaks: If you see leaks or other damage, replace the shock absorbers in a timely manner to avoid major problems in the suspension system.

summary

Car shock absorbers are important components that ensure a comfortable and safe ride. They absorb the impact of road irregularities, keeping the car balanced and stable, reducing excessive bump vibration and ensuring solid tire grip on the ground. Regular maintenance and timely replacement help extend the life of shock absorbers and ensure optimal vehicle performance and safety. The condition of shock absorbers is directly related to the stability and ride comfort of your vehicle, which is why it is important to maintain them on time and replace them when necessary.