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How to change a car tyre or use a repair kit

By Adrian Porter

Got a flat tyre? Our videos and simple step-by-step guides can show you how to change a tyre or how to use a tyre repair kit.

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Thwump-thwump-thwump-thwump... if you've heard that noise before while driving, you know it means one thing: you've got a flat tyre.

But there's no need to panic, and you may not need to call out a breakdown service either; changing or repairing a tyre is easier than you might think. Read on to learn how to change a tyre by hand, or fix a tyre with a tyre repair kit.

Is this the last straw for your current car? If you're considering buying a new one, discover the ones we recommend by viewing our Best Buys.

What to do if you have a puncture

If you hit an obstacle with a wheel, or a nasty pothole, the tyre may deflate quickly. You’ll likely feel a tug on the steering wheel and will probably hear it as well – a bang followed by a repeating ‘thwump-thwump’ sound.

If the tyre is deflating slowly, due to a nail or other sharp object stuck in the tyre, the steering may just feel heavier than usual or drag to one side.

Either way, you need to pull over and stop as soon as possible, but try to do so somewhere safe, such as a lay-by or side street, and try to avoid stopping on a busy or winding road.

If you’re on a motorway or dual carriageway, pull as far over to the left of the hard shoulder as you can to maximise the distance between you and moving traffic, while still giving yourself room to access the flat tyre.

Turn your engine off, put your hazard lights on, engage the handbrake and put the car into first gear (or 'park' if you drive an automatic). Make sure everyone is out of the car, safely away from the road, and put a warning triangle on the road if you have one.

What you do next will depend on whether your car has a spare tyre or, as many modern cars do, a tyre repair kit. It will also depend how badly the tyre is damaged: repair kits only work with small holes, so if you can see a visible slash in the tyre and have no spare, you should call a breakdown service.

How to change a tyre safely

Here's our video guide to changing a tyre. If you’re in an area with limited connection and can't see the video, our written step-by-step guide is below.

Changing a tyre in five easy steps

  1. Firstly, get out your spare wheel and tools, including a jack. They'll normally be found in the boot of the car, under the boot floor. Then grab your instruction manual, and thumb through it to locate the car's jacking point. The manual may also have instructions on how to change a tyre.
  2. Are you absolutely sure your handbrake is fully engaged and the car is in gear? If so, raise the car up by placing the jack under the jacking point closest to the wheel you're going to change and rotate the jack's handle clockwise.
  3. Once the tyre you're changing has cleared the ground, remove any trim that covers the wheel nuts, or ‘studs’ (bolts). Then use the wrench provided, and the special key if your car has locking wheel nuts, to remove them completely.
  4. With the fixings removed, you should now be able to remove the wheel with the puncture and replace it with your spare. Be careful – a car wheel is quite heavy.
  5. Reattach the wheel nuts and then lower the car to the ground. Once the car is lowered, tighten up the nuts, ideally working in a diagonal pattern. So, if your car has five nuts arranged in a star shape (which is quite common), tighten the first one, then move to the third, fifth, second and, finally, the fourth.

Congratulations, you've just changed a tyre.

What next for my car tyre?

Most spare wheels supplied with cars are only suitable for use at low speeds, often up to a maximum of 50mph, so you’ll need to get the original tyre replaced or repaired as soon as you can.

Even if it isn't limited to a certain speed, we suggest you still visit a garage so they can slacken off and then retighten the wheel fixings to exactly the right torque (tightness).

How to use a tyre repair kit

Many cars are now sold without a spare wheel and are instead supplied with an emergency tyre repair kit. These consist of a compressor powered from the car's 12V socket (or cigarette lighter), plus a bottle of sealant, usually liquid latex. Using a repair kit is fairly fuss-free, but it's only a temporary measure. Find out how to use one in our video, or scroll down further for a simple step-by-step written guide.

How to use a tyre repair kit in four easy steps

  1. Follow the same procedure for stopping safely as described above. Grab your repair kit – it's usually found under the boot floor.
  2. In most cases, using it is simply a case of connecting the bottle of latex to the tyre valve. Most bottles are pressurised, so the latex will flow through the valve into the tyre.
  3. Once inside the tyre, the latex should start to seal the hole. Now, connect the compressor to the 12V socket. Start the engine, then the compressor, and pump up the tyre. Simple as that.
  4. If the hole does not seal immediately, disconnect the compressor and try driving the car forwards or backwards a few metres to spread the sealant around the inside of the tyre. Then reattach the compressor and try again.

A tyre repair kit will often get you out of immediate trouble but is no good for holes larger than about 4mm. If you have a serious blowout or have damaged a tyre sidewall, you will have to call a breakdown service. These are the breakdown services we recommend.

Remember that a repair kit is only a temporary solution. Go to a garage to get your tyre repaired or replaced as soon as possible. Keep your speed below 50mph until then.

Top tip: tyre repair kits often have ‘best before’ dates, after which the sealant dries up and must be replaced. Check the date on yours and put a note in your diary to replace it when necessary.

Car tyre safety tips

Minimise tyre wear

To get the maximum mileage from your tyres, avoid harsh braking, rapid acceleration and fast cornering – all of these will increase wear.

Remove any stones or debris wedged in the tread, and keep an eye out for any cuts or bulges. These can be signs of imminent failure.

Check your car tyres regularly for excessive or uneven wear. Remove any stones or debris wedged in the tread, and keep an eye out for any cuts or bulges. These can be signs of imminent failure.

If you hit a kerb or bad pothole, you should make sure you haven't damaged a wheel. If the rim is scuffed, has it caused any sharp or rough edges? Any damage close to the tyre’s sidewall should be repaired at once, and you should ask a garage to rebalance the wheel afterwards.

Minimum tread depth

By law, your car tyres must have a minimum of 1.6mm of tread in a continuous band across three quarters of the width of the tyre.

However, tyre performance deteriorates well before the legal minimum depth is reached, particularly in wet weather. This is because the volume of the shallower tread grooves is reduced, so they are less capable of dispersing surface water from the road.

Don't wait for the MOT test to buy new tyres. Check your tyres regularly and consider buying new ones when the tread depth reaches 3mm.

Check your tyre pressures

You should check the pressure of each car tyre (including the spare) every couple of weeks or so – depending on your mileage, try to get into the habit of doing it every second fuel stop or similar.

Your car's handbook will tell you the correct tyre pressures, or you may find them printed on a sticker inside the driver or passenger door. Some modern cars have built-in tyre pressure monitors, but we recommend regular manual checks as well.

We also highly recommend you check pressures before a long motorway run because incorrect pressures can have a major impact on stopping distances, fuel economy and tyre wear.

Look after your spare tyre

The only thing worse than getting a puncture is when you go to fit the spare and discover that it has also gone flat. Check the spare regularly for pressure and condition, because if your spare is old, the rubber may begin to perish, resulting in potentially dangerous cracks in the tread or sidewalls.

If your car has a temporary ‘space-saver’ spare tyre, which are usually much narrower and designed simply to get you home, it will usually need to be inflated to a much higher pressure than a standard tyre. Check your owner's handbook for details.

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