Symptoms of a broken coil spring and should you still drive

Coil springs are a vital part of a vehicle's suspension system, helping to provide stability, support and a smooth ride. They’re designed to absorb shocks and vibrations from the road.

Keep reading for more information on the different types of coil springs, what to do if they break and the cost of repair.

What is a coil spring on a car?

Coil springs are a key part of a vehicle. They support the weight of a vehicle, provide stability and keep it at the appropriate height on the road. The springs work with the suspension to absorb impact when you drive on uneven roads. As your car ages, so do the coil springs – but routine checks will help them last longer.

Coil springs play a part in protecting your vehicle by:

• Making sure it maintains the correct height, so you’re always aware of how much clearance is needed
• Protecting the vehicle structure by softening the ride over potholes, speedbumps and uneven roads

There are two kinds of coil springs on a vehicle:

1. Linear – A linear coil spring is a type of coil spring that has a constant spring rate. Regardless of how much force is applied, the spring compresses and extends at a constant rate. Linear springs are commonly used in the suspension system of cars, trucks and motorcycles.
2. Regressive – Regressive coil springs have a variable spring rate. This means that the spring rate changes as the spring compresses or extends. Which means they are softer at the initial stage of compression or extension and become stiffer as they travel further. This ensures a comfortable ride over small bumps while maintaining stability and control over larger bumps. Regressive coil springs are mostly used in sports cars or racing vehicles.

What causes your car’s spring to break?

Typically coil springs last 60,000 to 90,000 miles before they need to be replaced. However, they can break due to:

1. Corrosion – To do their job, coil springs are constantly expanding and compressing. This action causes the plastic coating that protects the wire to crack – exposing it to the elements. Rain, snow and salted roads during winter cling to the wire and over time cause it to corrode and break.
2. Blown tyres – A blown tyre throws a vehicle off balance. This makes the suspension on other parts of the vehicle work harder to shoulder the weight.
3. Hydraulic fluid leak – Worn or leaking shock absorbers, will make the spring work harder and compress more, potentially leading to spring failure.

What symptoms and noises do broken springs have?

Signs that a coil spring is broken include:

• Uneven tyre wear
• The ride height may be uneven and sag
• The suspension system may make unusual sounds like clunks or squeaks
• Decreased handling capabilities which can make driving feel bumpy and unstable ride

Can I drive my car with a broken coil spring?

No, driving with broken coil springs puts you and other drivers on the road at risk. It can lead to a puncture, as the broken spring can travel down past its mounting and pierce the side wall of the tyre.

What are the repair costs of a broken coil spring?

A broken coil spring cannot be repaired, it must be replaced.

The price of replacing a broken coil spring depends on what type of vehicle you own. Coil springs designed for compact cars are generally less expensive than those made for big SUVs.

Prices also differ between the front and rear coil springs. The average cost of replacing a front coil spring is £225 and £172 for the rear coil spring. Factors that affect the cost of replacing a coil spring include:

• Model and make of the car
• The amount of labour required
• Whether other parts need to be replaced
• Buying parts from Original Equipment Manufacturers (OEM)

How quickly should you replace a broken coil spring?

It’s important that you immediately speak to a certified mechanic if you have a broken coil spring.

A broken coil spring can cause an accident and you’re at a higher risk of a tyre blowout or the broken spring piercing the tyre. This increases the risk of accidents, especially if the spring causes the car to lose control at high speeds or while making turns.

If you experience issues with your car's coil springs, get them checked and replaced by a professional mechanic immediately.

Do coil springs need to be replaced together?

Coil springs should be replaced in pairs; you don’t need to replace all four at the same time. For example, if a front spring is broken, then you must replace the other one as well. This helps to maintain a balanced suspension system.

Is a broken coil spring an MOT failure?

Your vehicle will fail its MOT if any of the coil springs are broken, cracked or fractured.

Coil springs are a part of the suspension and play an important role in keeping your car stable as you drive. It’s one of the main components that’s checked during an MOT test is the vehicle’s suspension system.

If you see signs of a broken or corroded coil spring, don’t drive your car it needs to be recovered and replaced where it is.

How long should my suspension and coil springs last?

Coil springs can last between 50,000 and 100,000 miles before they need to be replaced. The lifespan of coil springs is influenced by various factors such as driving conditions, vehicle make and quality of the springs.

To ensure a safe and smooth ride, it's essential to schedule routine maintenance and inspections that can help prolong the lifespan of your suspension system and coil springs.