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Demystifying Shock Absorbers & FAQs

  • Shocks-Tips/Guides-Shocks

Shock absorbers, also known as dampers, are an essential component of a vehicle's suspension system. They play a crucial role in ensuring a smooth and comfortable ride while maintaining control and stability on the road. As a vehicle owner, understanding the basics of shock absorbers can help you make informed decisions about their maintenance and replacement.

In this article, we will address some of the most frequently asked questions about shocks and struts, providing you with valuable insights and information.

What are Shock Absorbers and What is Their Purpose?

Shock absorbers are hydraulic devices that are designed to absorb and dissipate the energy generated by the up-and-down motion of a vehicle's suspension system. Their primary function is to dampen the oscillations caused by road irregularities, ensuring a smoother ride and better control over the vehicle.

They work by converting the kinetic energy of suspension movement into thermal energy, which is then dissipated through the hydraulic fluid.

Shock absorbers play a crucial role in controlling the vehicle's body motion, ensuring a smooth and comfortable ride while maintaining traction and handling.

How Do Shock Absorbers Work?

Shock absorbers consist of a piston that moves through a cylinder filled with hydraulic fluid. They work by converting the kinetic energy of the suspension movement into thermal energy, which is then dissipated through the hydraulic fluid inside the shock absorber. As the suspension moves up and down, the piston inside the shock absorber is forced to move through the hydraulic fluid, creating resistance and dampening the oscillations, preventing excessive bouncing and ensuring a controlled and stable ride

What is the Difference Between Shocks and Struts?

While shocks and struts serve similar purposes, they are different components of the suspension system. Shocks are individual components that are connected to the suspension system, while struts are a structural part of the suspension system that incorporates the shock absorber and other components, such as the coil spring. Struts are commonly found on the front suspension of many modern vehicles.

Do I need a wheel alignment after replacing front shocks?

Failing to perform a wheel alignment after replacing front shocks or struts can result in premature tyre wear, decreased steering responsiveness, and potential safety issues due to improper tyre contact with the road surface.

Does suspension affect alignment?

Yes, the suspension system of a vehicle directly affects wheel alignment. The suspension components, including shocks/struts, springs, control arms, and bushings, are responsible for maintaining the proper geometry and positioning of the wheels relative to the vehicle's body. Any changes or wear in these components can cause misalignment of the wheels, leading to various issues.

Is suspension alignment the same as wheel alignment?

No, suspension alignment and wheel alignment are not the same thing, although they are closely related. While a wheel alignment is primarily focused on adjusting the angles of the wheels, a suspension alignment addresses the overall geometry and positioning of the suspension system, which directly impacts the wheel alignment. If the suspension components are worn or misaligned, it can cause the wheels to become misaligned, even after a proper wheel alignment is performed.

Does wheel alignment affect acceleration?

No, wheel alignment does not directly affect a vehicle's acceleration. Wheel alignment refers to the adjustment of the angles of the wheels relative to each other and the vehicle's body, ensuring that the wheels are properly aligned and tracking correctly. The primary purpose of wheel alignment is to optimise tyre wear, handling, and stability, but it does not have a significant impact on the vehicle's acceleration performance.

The acceleration of a vehicle is primarily determined by factors such as engine power, torque, weight, and gearing ratios, rather than wheel alignment. However, improper wheel alignment can indirectly affect acceleration in certain situations.

How Does Rust Form on a Car's Suspension System?

Rust formation on a car's suspension system typically begins with the breakdown of the protective coating or paint on the metal components. Once the bare metal is exposed, it reacts with oxygen and moisture in the air, forming iron oxide, commonly known as rust . This process is accelerated in the presence of salt, which acts as an electrolyte and facilitates the chemical reaction.

Can Bad Shocks Cause Uneven Tyre Wear?

When shock absorbers become worn or fail, they can no longer effectively dampen the suspension movement, leading to excessive bouncing and uneven weight distribution on the tyres. Uneven tyre wear is one of the most common signs of worn shock absorbers. When shocks are bad, the tyres may experience cupping or feathering of the tread, where the tread wears down unevenly across the tyre's surface. This uneven wear pattern is caused by the tyres bouncing and losing proper contact with the road due to the lack of suspension control.

Why is The Steering Wheel Off-Centre After Strut Replacement?

When new struts are installed, they may have slightly different dimensions or mounting positions compared to the old ones. This can cause the suspension to settle in a different position, leading to a change in the alignment angles. As a result, the wheels may no longer be perfectly parallel to each other or aligned with the vehicle's centreline, causing the steering wheel to appear off-centre.

How Do Vehicles Lose Their Wheel Alignment?

  • Worn Suspension Components: Over time, suspension components such as shocks, struts, control arms, and bushings can wear out, leading to changes in the suspension geometry and causing the wheels to become misaligned.
  • Hitting Potholes or Curbs: Striking potholes, curbs, or other road obstacles with significant force can knock the wheels out of alignment by damaging suspension components or altering their positioning.
  • Accidents or Collisions: Even minor accidents or collisions can cause suspension damage, resulting in misaligned wheels.
  • Improper Repairs or Modifications: Improperly performed repairs or modifications to the suspension system, such as replacing components with incorrect parts or improper installation, can lead to wheel misalignment.
  • Uneven tyre Wear: Significant uneven tyre wear can cause changes in the suspension geometry, leading to wheel misalignment over time.
  • Overloading or Improper Loading: Carrying excessive weight or improperly distributing the load in a vehicle can put additional stress on the suspension system, potentially causing misalignment.
  • Age and Wear: Over time, the natural wear and tear on suspension components can cause them to become loose or worn, resulting in changes to the suspension geometry and wheel alignment.

How Often Should Shock Absorbers be Replaced?

The lifespan of shock absorbers can vary depending on several factors, including driving conditions, vehicle usage, and the quality of the shocks themselves. As a general rule, it is recommended to replace shock absorbers every 80,000 to 160,000 kilometres or every 4 to 5 years, whichever comes first. However, it is essential to inspect them regularly for signs of wear or damage and replace them as needed.

When to Replace Shock Absorbers?

Most manufacturers recommend replacing shock absorbers every 50,000 to 100,000 miles, depending on driving conditions and vehicle usage. However, it's essential to inspect shock absorbers regularly and replace them if any signs of wear or damage are present.

Replacing shock absorbers in pairs (front or rear) is recommended to maintain balanced handling and ride quality.

What are the Signs of Worn Shock Absorbers?

Some common signs of worn shock absorbers include:

  • Excessive bouncing after hitting a bump or pothole
  • Nose-diving during hard braking or excessive body lean during turns
  • Difficulty controlling the vehicle during braking or turning
  • Unusual noises or rattling sounds from the suspension system
  • Uneven tyre wear or cupped tyre patterns, indicating poor suspension control
  • Fluid leaks or visible damage to the shock absorber body

Can I Replace Shocks Myself or Should I Seek Professional Help?

While it is possible to replace shock absorbers yourself if you have the necessary tools and mechanical skills, it is recommended to seek professional help from a qualified mechanic or a reputable auto repair shop. Improper installation or the use of incorrect parts can compromise the safety and performance of your vehicle's suspension system.

What are the Benefits of Replacing Shock Absorbers?

  • Improved ride quality and comfort, reducing fatigue during long journeys
  • Enhanced vehicle control and stability, especially during emergency manoeuvres or sudden stops
  • Better handling and responsiveness, improving overall driving experience
  • Increased safety by maintaining proper traction and braking performance

How to Choose the Right Shock Absorbers?

While you may consult with a professional mechanic, you should consider the vehicle's make, model, and driving conditions and opt for high-quality, reputable brands that offer appropriate damping characteristics for your driving needs. Also refer to your vehicle's owner manual for recommended shock absorber specifications.

How to Maintain a Car’s Suspension?

  1. Regular Inspections: Visually inspect the suspension components, such as shocks, struts, springs, control arms, and bushings, for signs of wear, leaks, or damage during routine maintenance or when experiencing any unusual noises or handling issues.
  2. Shock Absorber and Strut Replacement: Shock absorbers and struts are wear items that need to be replaced periodically, typically every 80,000 to 160,000 kilometres, depending on driving conditions and the manufacturer's recommendations. Worn shocks and struts can cause excessive bouncing, poor handling, and uneven tyre wear.
  3. Spring Inspection: Check the condition of the suspension springs for signs of sagging, cracking, or rust. Worn or damaged springs can affect the vehicle's ride height and handling characteristics.
  4. Bushing and Ball Joint Replacement: Inspect and replace worn bushings and ball joints, which are essential for proper suspension articulation and alignment. Worn bushings can cause excessive play and noise in the suspension system.
  5. Wheel Alignment: After replacing suspension components or if you notice uneven tyre wear, it is recommended to have a professional wheel alignment performed. Proper wheel alignment ensures optimal tyre wear, handling, and fuel efficiency.
  6. Lubrication: Lubricate suspension components, such as ball joints and control arm bushings, according to the manufacturer's recommendations to prevent premature wear and ensure smooth operation.
  7. Rust Prevention: Inspect the suspension components for rust and apply rust-preventive coatings or undercoating to protect them from moisture and salt exposure, which can lead to corrosion and component failure.
  8. Suspension Modifications: If you plan to modify your car's suspension, such as lowering or installing performance shocks or springs, ensure that the components are compatible and properly installed to avoid compromising the vehicle's handling and safety.


Shock absorbers play a vital role in ensuring a smooth, comfortable, and safe driving experience. By understanding their function, recognising signs of wear, and following recommended replacement intervals, drivers can maintain optimal vehicle performance and handling. Regular maintenance and inspections, along with choosing the right replacement shock absorbers can help extend their lifespan, enhance overall driving satisfaction, and improve safety on the road.

Supa Quick is dedicated to road safety – visit your nearest Supa Quick service centre for a free vehicle safety check*.

*The Supa Quick Free Safety Check may vary from dealer to dealer.

Also read:

Know Your Shock Absorbers

Types of Shock Absorbers

Learn About Shock Absorbers

Do Worn Shocks Affect Tyre Wear and Tear?

Ensure Your Shocks Work Properly to Combat Potholes in South Africa

How Worn Shocks Puts Your Safety at Risk 

Disclaimer: This information is for educational, or entertainment purposes only. It must not be construed as advice, legal, financial, or otherwise. We do not make any warranties about the completeness, reliability, and accuracy of this information.


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