Are cracked tyres illegal?

Tuesday 17th May 2022

If you have small cracks on the wall of your tyre, this is not illegal - however, it is a sign that your tyres may need replacing soon. If the cracks on the tyre are substantial, this could result in a tyre blowout and can be extremely dangerous for drivers and others on the road.

For clarity on whether the cracks in your tyres are substantial or not, pop into your local Formula One Autocentre and speak to one of our experts.

What are ‘cracked’ tyres?

Cracked tyres refer to when there is damage to the tyre wall, such as bulges or cracks. This can increase the likelihood of a tyre blowout, especially if you are driving at high speeds, such as motorway driving. Cracked tyres typically can’t, and shouldn’t be, repaired – replacing your tyres is the best option to be safe and legal on the roads.

Why do tyres crack?

There are a number of reasons why tyres can crack or wear, including:

• Age – the older your tyre gets, the more it will experience natural wear. The rubber on the outside of the tyre naturally weakens over time, which causes your tyres to harden and become brittle, causing cracks in the rubber.
• Water – although rubber is waterproof, after driving on wet roads for prolonged periods of time, water can still penetrate the tyre. This can wear the tyre from the inside out, as the water can then expand and contract, causing cracks to appear.
• Heat – the rubber on the outside of the tyre expands and contracts in different temperatures, which can cause the tyre to weaken over time. It’s important to note that UV rays can also have this effect on tyres.
• Tyre pressure – if your tyres are not inflated correctly, this can also cause cracks and cuts to appear. Overinflated tyres can add extra pressure to the tyre wall whereas underinflated tyres can create more heat when driving, which causes friction.

Can cracked tyres fail an MOT?

Yes - the condition of your tyre can be a deciding factor whether your vehicle passes or fails its MOT. Any cuts, bulges, tears or cracks in the sidewall can be a sign of serious tyre damage – and will be a reason for your vehicle to fail its MOT test. Learn more about the most common reasons for MOT tyre fails from our guide.

How to prevent tyres from cracking

There are a few ways that you can make your tyres last longer, and prevent them from cuts, bulges and cracks:

• Correctly inflated tyres – ensure your tyres are constantly inflated to the right tyre pressure.
• Parking – as UV rays can affect the condition of your tyre, you could make a conscious effort to try and park in the shade, or in a garage, away from the heat of the day.
• Safe driving – ensuring your driving style isn’t affecting your tyre’s condition is a good way to make your tyres last longer. For example, this could be avoiding potholes where possible, avoiding bumpy or rough terrain, and gentle acceleration.

For more information about how to improve the life of your tyres, our dedicated guide has you covered.

If you think your tyres need replacing, find new tyres to buy online today. Locate your nearest Formula One Autocentre and pop in for your tyre fitting!