What makes your car’s tyres illegal?
It's easy to overlook your car's tyres, but they are vital for your safety on the road, and you're risking a hefty fine if you drive around on tyres that are illegal...
Far too many people simply have tyres fitted to their car and forget about them. The stats throw this into sharp relief, because tyres are the main cause of a car failing its annual MOT test in its first seven years. In fact, defective tyres account for more than two million MOT failures each year.
In spite of this, 35% of the cars on UK roads are driving on tyres that are at least 8psi below the recommended pressure. Such carelessness doesn't only cost you money, it is a huge mistake because tyres are the main component that will get you out of trouble in an emergency. Conversely, the failure of a faulty tyre on a busy road could prove very dangerous - according to tyre charity, Tyresafe,
How can having poorly maintained tyres affect your car?
Cars are designed and built to perform at their very best when tyres are new and have plenty of tread on them, but worn tyres can bring about a dramatic reduction in both your car’s performance and its safety. The problem is that when you drive a car on a daily basis, this drop-off in performance can be so gradual that you don’t notice it.
For example, data from tyre safety experts TyreSafe shows that in the wet at 50mph, a tyre with 1.6mm of tread will take 6.9 metres longer to stop than a tyre with 8mm of tread. Think about it – that’s much more than the width of a pedestrian crossing. At 70mph, your stopping distance is increased by 27m – more than half the length of an Olympic swimming pool.
These are stats on tyres that are still just legal. Let the tyre wear down even further and not only will you not be able to stop in a straight line, but your car won’t go round corners are intended either.
Tyres get a hard life, and often have to endure the odd kerb strike when parking, or as is commonplace on today’s roads, hitting a pothole, which can cause a puncture.
Either can damage the carcass of the tyre, and cause a split in the tread or a bulge in the sidewall. These can cause the tyre to fail at any second, and the last thing you want is to end up with a shredded tyre at the side of a ‘smart’ motorway or on a dark and twisty road. You’ll be in serious danger in each scenario, and that’s why regularly checking your tyres for tread depth and damage is essential.
How to check your car’s tyres
Checking all four of your car’s tyres should take you around 10 minutes, maximum. To do this properly, you’ll need to invest in a tyre pressure gauge and a tread depth gauge, and then you’ll need to ensure that the tyres are cold, so do this before you start your motoring day, or leave the tyres to cool down for around 45 minutes after you’ve stopped driving the car. This is because when you drive, the air in the tyre heats up, increasing the pressure, so if you try to measure it just after a journey you’ll end up with an incorrect reading.
Once the tyres are cold, remove the dust caps from all four valves, then find out what the pressure should be by checking the sticker that’s on either the inside of the fuel filler cap or trailing edge of the driver’s door aperture. Use your tyre pressure gauge to ensure that all four tyres are at the right pressure, and if they’re not pump them up either with a portable tyre inflator or using one at a fuel station until they’re right.
For a tyre to be legal, it must have a minimum of 1.6mm of tread across the middle 75% of its width, so measure the depth at three separate spot across the width, then roll the car forward and check it again.
And finally, use your eyes and hands to feel the surface and sidewalls for any cuts or bulges – and don’t forget to reach around and feel the inner sidewall.
What to do if your tyres are illegal?
If your tyres are illegal, you can’t simply drive to the nearest tyre outlet, because if you’re stopped by the police you’ll still be deemed to be driving illegally even if you can show you have an appointment booked.
Matters will be even worse if you’re involved in an accident on the way to the tyre outlet, because your insurance company could refuse to pay out on any claim. It’s not worth the risk.
One option is to jack up the car, place it on axle stands for safety, then remove the offending wheels and get a friend to take them and you to the tyre outlet (and hopefully home again once the tyres have been replaced on the wheels).
There is another way – call up one of the many mobile tyre-replacement services and get them to come to you and replace the tyres. You might have to pay a bit more for such a service, but it’ll save you a huge amount of hassle.
What happens if the police stop you and your car tyres are illegal?
You’ll be liable to be prosecuted, and the severity will depend on how many of your tyres are illegal, and by how much.
If the tyres are on fractionally over the illegal line, then you’ll likely get a Fixed Penalty Notice and some points on your licence.
However, if your tyres are badly illegal and you pose a serious risk to other road users, then you’ll face prosecution. So, you can be fined a maximum of £2500 and be liable for three penalty points – per tyre. So, you could face a huge £10k fine and an automatic ban under the totting-up process.
And the police don’t have to stop there. If you’re caught doing something stupid in your car with dodgy tyres, you could face imprisonment.
Paying a bit extra for a mobile fitter doesn’t seem quite so onerous after all that, does it?
Where can you buy tyres?
There’s a vast range of places from which you can buy new tyres, so there’s no excuse for having dodgy rubber on your car.
You can order tyres without even leaving the comfort of your sofa, thanks to online services such as Blackcircles.com. These can either deliver the tyres to you, or to a local tyre fitting outlet.
There are numerous nationwide fast-fit outlets, such as Kwik Fit and ATS Euromaster, as well as a whole range of small, local tyre-fitting businesses. If you take your car to a trusted garage for servicing, it will also be able to replace tyres for you.
And finally, there are plenty of mobile tyre-fitters that come to your home or place of work, and can fit the tyres for you in a very short time.
FAQs
What is a legal tyre?
A legal tyre is one that has 1.6mm of tread across the central 75% of its width, and which has no splits or bulges.
How long should tyres last?
This is largely dependent on the type of driving you do, and your driving style.
If you’re a gentle driver, then you can expect tyres to last up to 40,000 miles. The tyres on the driven axle will wear faster than the ones on the un-driven axle, so in a front-wheel-drive car the fronts will wear much faster than the rears, and vice-versa in a rear-drive car. When the tyres start to wear, it’s good to swap them from front to rear so you maximise the usage of all four tyres.
However, even if you’re gentle, keep an eye on your tyres to make sure the tyre surface isn’t breaking down simply through age. A tyre should last up to five years, but will require monitoring for age-related issues thereafter.
Are tyres that are more than 10 years old illegal?
No, but the chemical make-up of the tyre could start to break down due to age and being exposed to climatic conditions, so you need to keep an eye out for signs of cracks or splits.
Should I replace one or more tyres at once?
Yes, you should always replace both tyres on the one axle at the same time, or you’ll end up with a grip imbalance. They’ll tend to wear out at the same rate anyway, so it’s likely that you’ll need to replace them both.
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