Are Struts Part of the Suspension System?

Confused about what a strut is and how it fits into your car? You’re not alone. Let’s clarify its vital role in your vehicle’s suspension system.

Yes, struts are a critical, structural part of the suspension system. In many modern cars, they do more than just absorb bumps; they support the vehicle’s weight, provide a pivot point for steering, and locate the wheel assembly.

The term "strut" is often used interchangeably with "shock absorber," but they are fundamentally different components. As a specialist manufacturer and supplier of all types of suspension parts since 1998, including shock absorbers, control arms, and the bushings that work with these systems, we at GSW Autoparts want to make this distinction clear. A strut is not just a part of the suspension; in many vehicles, it’s the central structural hub of the entire system.

Are struts part of the suspension?

Let’s start with the most direct question: Are struts a component of the vehicle’s suspension system? The answer is an emphatic yes.

Absolutely. Struts are a primary and structural component of the suspension, most commonly found in the "MacPherson strut" design. Unlike a simple shock absorber, a strut is an integral part of the vehicle’s chassis and steering system.

It’s crucial to understand the difference between a shock absorber and a strut, a topic we are very familiar with at GSW Autoparts.

• A Shock Absorber’s Role: A traditional shock absorber has one job: to dampen the oscillation (bouncing) of the vehicle’s springs. It’s a hydraulic component that controls movement but does not support the vehicle’s weight.

• A Strut’s Role: A strut does the damping job of a shock absorber, but it also does much more. A strut is a major structural assembly that combines the damping function¹ with other critical roles. It replaces the upper control arm in a conventional suspension, and the entire assembly (strut, spring, and top mount) has three key functions:

  1. Damping: An internal damper cartridge controls spring bounce, just like a shock absorber.
  2. Structural Support: The strut body itself is a load-bearing component that supports the vehicle’s weight via the coil spring seated upon it.
  3. Steering Pivot: The strut assembly² serves as the upper pivot point for the steering system, allowing the entire wheel assembly to turn.

If you were to remove a simple shock absorber, the vehicle would still be held up by its spring. If you remove a strut, that corner of the vehicle’s suspension would collapse.

How much does it cost to replace a strut?

If you’ve been told you need new struts, the cost is likely your next concern. This is a significant but vital repair.

In the UK, the cost to replace a pair of front struts in 2025 typically ranges from £300 to £700. This price includes the strut assemblies, labour, and the essential wheel alignment that must be done afterwards.

The cost of strut replacement is a combination of parts, labour, and follow-up services. At GSW Autoparts, we supply a vast range of high-quality components that offer excellent value. Here’s a typical cost breakdown in the UK:

• Parts Cost: A single complete strut assembly (which includes the strut, coil spring, and top mount) can cost anywhere from £80 to over £200 for a quality aftermarket part, depending on the vehicle make and model. OEM parts from a dealership will be more expensive. It is always recommended to replace struts in pairs (both front or both rear) to ensure balanced handling and safety.
• Labour Cost: A garage’s hourly rate in the UK typically falls between £60 and £120. Replacing a pair of front struts is a significant job that can take between 2 to 4 hours, depending on the vehicle’s complexity and if any bolts are seized.
• Wheel Alignment: This is not an optional step. Because a strut is a key part of your steering and suspension geometry, replacing it will affect your wheel alignment³. A full four-wheel alignment is necessary to ensure your car drives straight and to prevent rapid tyre wear. This service usually adds another £50 to £100 to the final bill.

So, for a typical family car, budgeting for £300 to £700 for a pair of front struts is a realistic expectation.

How much does it cost to fix a suspension?

"Fixing the suspension" is a broad term. The cost depends entirely on what specific part has failed.

The cost to fix a car’s suspension in the UK can range from under £100 for a simple broken link to over £1,000 for a major overhaul involving multiple components. A proper diagnosis is key to determining the cost.

As a manufacturer of a comprehensive range of suspension components, from control arms to bushings, we at GSW Autoparts know that a "suspension fault" can mean many things. The final repair cost is tied to the specific failed part. Here are some common suspension repairs and their typical cost ranges:

• Stabiliser Bar End Link Replacement: Often the source of clunking noises. Cost: £80 – £150.
• Rear Shock Absorber Replacement (Pair): For non-strut systems. Cost: £200 – £400.
• Coil Spring Replacement (Pair): If a spring has snapped (a common MOT failure). Cost: £200 – £450.
• Control Arm Replacement (Single): If a bushing or ball joint has failed. Cost: £150 – £400+.
• Strut Replacement (Pair): As mentioned, this is a more involved job. Cost: £300 – £700+.

A small knocking noise could be a simple fix, whereas a combination of worn struts, control arms, and links could lead to a bill exceeding £1,000. This is why a thorough inspection and accurate diagnosis from a trusted garage are so important.

What happens when a strut goes bad?

How can you tell if your struts are wearing out? Your car will provide several clear warning signs that its ride and handling are compromised.

When a strut goes bad, you will notice symptoms like a bouncy and unstable ride, knocking or clunking noises over bumps, uneven "cupped" tyre wear, the front of the car "nose-diving" under braking, and visible fluid leaks from the strut body.

A failing strut can no longer control the spring’s movement or properly support the vehicle’s weight and geometry. From our experience at GSW Autoparts, these are the key symptoms to watch for:

• Bouncy Ride⁴: This is the classic sign of a worn damper. After hitting a bump, the car will continue to bounce multiple times instead of settling immediately.
• Noises: A worn strut top mount can cause a knocking or clunking sound when going over bumps or turning the steering wheel.
• Instability: The vehicle may feel less stable on the road, swaying in crosswinds or rolling excessively in corners. You may also notice the front end "nose-diving" when you brake, or the rear end "squatting" when you accelerate.
• Uneven Tyre Wear⁵: The bouncing caused by a bad strut can lead to a specific type of scalloped or "cupped" wear pattern on your tyres.
• Visible Fluid Leaks⁶: The strut is a hydraulic component. If you can see oily fluid leaking down the side of the strut housing, its internal seals have failed and it needs immediate replacement.

These symptoms are not just uncomfortable; they are safety issues that would likely result in an MOT failure.

Can you drive with a broken suspension strut?

What if a strut isn’t just worn, but completely broken? This is a much more serious and dangerous situation.

No, it is extremely dangerous and illegal to drive with a broken suspension strut. A broken strut means a critical structural component has failed, which can lead to a complete loss of vehicle control. The vehicle must be towed.

At GSW Autoparts, we must be absolutely clear on this point: there is a huge difference between a "worn" strut and a "broken" one. A worn strut makes for a bouncy, unpleasant, and less safe ride. A broken strut—for instance, if the main piston rod has snapped, the housing has cracked, or the top mount has completely separated—is a catastrophic failure.

Because the strut is a primary load-bearing and locating component, a break means:

• The suspension on that corner can collapse, causing the car’s body to drop onto the tyre.
• The wheel’s position is no longer controlled, leading to a complete loss of steering control and stability.
• The vehicle is undrivable and presents an immediate danger to you and other road users.

Driving a vehicle in such a dangerous condition is illegal in the UK and would be one of the most serious MOT test failures. If you suspect your strut is broken, do not attempt to start the engine or drive the car. It needs to be safely recovered by a tow truck and taken to a garage for repair.

Conclusion

Struts are undeniably a core structural part of the suspension in many vehicles. Recognizing the signs of wear and understanding the safety implications are crucial for every driver.