Cracked tyres – why are my tyres cracking?

Cracked tyres – why are my tyres cracking?
Over its lifespan, your vehicle may suffer from a few issues that will need to be addressed – and a common problem relates to the health of your tyres.

Sometimes you may suffer a puncture, or feel the impact of driving with the incorrect tyre pressure – however another common issue is cracked tyres. But what are they? And what can you do to resolve the problem?

Tyre safety is an integral part of car maintenance, and shouldn’t be ignored. This will save you money in the long run, and keep yourself and all road users safe.

This guide looks into what you should look out for, the causes, and whether it is legal to drive with cracked tyres.

Are you concerned about your tyres? Check with your local mobile mechanic.

Causes for cracked tyres

Cracks can appear on the side and on the top of a tyre – and are a cause for concern for drivers as it can make a vehicle unroadworthy, dangerous and could lead to further problems with your vehicle.

There are many causes for cracked tyres – and many are preventable by some simple maintenance and being aware of the impact of road conditions.

In many cases there might not be a solution and you may have to look at buying new tyres and replace the damaged ones.

Below are the leading reasons why you might experience cracked tyres.


Over time, your tyres will start to have some wear and tear that could lead to several problems – including cracking.

Tyres are made up of rubber polymers, and after thousands of miles and months of being on the road, they naturally weaken.

This makes the outside of the tyre become hard and brittle, leading it to crack.

However, this can also happen if you leave a vehicle in a garage for a few years without driving it. It is actually better for the longevity of the tyre for the vehicle to be driven regularly as the chemical that prevents the tyre from drying out only works when the tyre is moving.

̕Knowing how to get the most out of your tyres can make them last longer.


Although rubber is largely waterproof, driving in wet conditions over a prolonged period of time can lead to it permeating the seal – causing the tyre to crack.

Once in the tyre, water can impact in a variety of wheels. It can alter the alignment, cause issues when braking and accelerating, and once the water expands it causes damage to the tyre.

The expansion and contraction over time will create new cracks and make the current ones worse until it makes the wheel incredibly weak.

Natural degradation

Rubber is a biodegradable, organic material that will break down over time no matter what.

Depending on the quality of the tyre when initially bought, the lifespan of it can vary.

More expensive tyres with a range of chemicals can slow down this process.

If you are worried about the tread on your tyres, then it is worth checking, as this could indicate degradation of the tyre.

UV rays and intense heat

Rubber polymers expand in the heat and contract in the cold. Over time, this can lead to cracking – and the intensity of the UV rays can have the same impact.

This combination – especially over a short period of time can drastically affect the tyre.

A simple way of making the tyre last longer is to keep your vehicle in a garage or out of the reach of the sun – but this is not always possible.

Tyre pressure

Have you recently checked your tyre pressure? If not, then it could lead to many problems with your tyres.

If your tyres aren’t inflated enough, then cracking will occur as the heat rises while driving. This is because more friction is being caused on the wheels. This can lead to cracking, bulging, and splitting.

The video below shows the correct way to check your tyre pressure.

Are cracked tyres dangerous?

Yes, cracked tyres are very dangerous and they should be dealt with immediately. If you have noticed cracked tyres, then you should get them replaced as soon as possible.

If only one tyre has suffered from a cracked tyre, then it is best to change your tyre and then drive to a local garage.

Tyre safety is a vitally important part of owning a vehicle.

The rigidity and strength of the rubber polymer needs to be maintained in order to keep you and your passengers safe.

Are cracked tyres illegal?

Cracked or damaged tyres are not necessarily illegal – but they are dangerous for you, your passengers and other road users.

If the tread doesn’t reach the legal limit, then they are illegal. Small tears and wear and tear should be addressed immediately before they create a more serious problem.

Never ignore the signs that your tyres need replacing.

Are cracked tyres an MOT fail?

Although it isn’t illegal to drive with cracked tyres – they will mean that your vehicle will fail its annual MOT.

Damage to the tyre wall will result in you needing to buy new tyres before you can head back out on the road

Can you fix cracked tyres?

Unlike many other car issues that can be resolved by either yourself or a mechanic – you should not attempt to fix cracked tyres.

As the structure of the tyre has been compromised – and cannot be repaired – the only option you have is to replace them as soon as possible.

How to make tyres last longer

Although you cannot fix cracked tyres, there are some preventative measures you can take to make your tyres have a longer lifespan.

Parking your vehicle on a flat surface and out of the sun/UV rays are two simple ways to prevent your tyres breaking down over a longer period of time.

Also, having the correct tyre pressure will ensure that they are in perfect condition to make your ride as smooth as possible – and prevent any cracks appearing.

If you are noting that the ride feels slightly uneven, then it could be down the balance of the wheels being off. They will need to be realigned in a local garage to prevent your tyres irregularly deteriorating.

Aggressive driving styles will lead to tyres breaking down a lot quicker than a calm attitude behind the wheel.

A little known trick for extending the life of your tyres is to rotate your front and rear tyres every 7,500 miles to even out the wear and tear.

Tyres cracked between tread

Below is an image of what you could expect to see if there is a crack between the tread in your tyre.

Tyres cracked on the side

The image below is an example of what a crack on the side of the of a tyre looks like

Bulging or balding tyres – what does this mean?

Cracked tyres are not the only dangerous damage your tyres could suffer from.

If your vehicle has a bulge on the side of a tyre, then it is due to air being pushed into a weaker part of the constriction of the tyre, causing it to expand.

Much like cracked tyres – get this sorted as soon as possible. The image below is an example of a bulging tyre.

A balding tyre is simply where the tread in the tyre has become smooth – and illegal.

This means there is less grip on the road, and can lead to a serious accident. Below is an image of a balding tyre.

Do you have any cuts in tyres?

Although most tyre damage is caused through wear and tear or through the way you drive your vehicle, you may also notice other issues with your tyre.

If there is a thin slit on the side of your tyre, then it could have been caused by a knife or sharp object.

If this is the case, then do not drive your car, as this will likely lead to the tyre wall splitting – potentially at a higher speed.

Should this happen to you, call the police, and let them know the situation.

Buying new tyres

Are you looking at getting some new replacement tyres? This guide to tyre buying will help you get all the information you need.

Check out RAC Tyres for more information.

We hope this guide has helped you get a greater understanding of cracked tyres – stay sage out on the roads.

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