What pressure should my car tyres be?
Keeping the right pressure in your tyres can save you a whole lot of money and time down the line, so it’s worth knowing what pressure they should be. But, how are you supposed to know?
We’ve outlined everything you need to know about tyre pressure in this blog.
Why should I check my car tyre pressure?
Regularly checking your tyre pressure is important for a few main reasons:
- Safety - Having your tyres at the wrong pressure can affect your handling, as too much or too little contact with the road will affect your grip. Low tyre pressure can also increase the risk of aquaplaning in wet conditions and increase the braking distance on dry roads. Tyres with too little air in them are also more prone to punctures and blow-outs at high speeds.
- Fuel consumption - Tyres with too little air in them cause your car to have to work a lot harder to maintain speed. This increases your fuel consumption and, so also your emissions.
- Longevity - If tyres don’t have the right air pressure, they can be prone to faster deterioration and weakening of the internal structure. This reduces the lifespan of your tyres and makes them less reliable.
If you’re wondering about how long parts of your car should last, you can check out our blog ‘How long should a car battery last in the UK?’
The impact of under-inflated tyres
If your tyres are under-inflated for an extended period of time, you’re likely to see a lot more wear on the inside and outside edges of the tread than you would otherwise. This is because the contact with the road will be uneven. Under-inflated tyres also increase the rolling resistance, so you’ll use more fuel as the car tries to compensate.
The impact of over-inflated tyres
If your tyres have too much air in them, they won’t have enough contact with the road. This will give you less traction through corners and longer braking distances. You’ll also likely see heavy wear on the central part of your tyre, as that’s all that’ll be touching the road.
How often should I check my car tyre pressure?
You should try to check your car tyre pressure pretty regularly, as most tyres tend to lose pressure over time naturally. It’s best to check your tyres every couple of weeks and before long journeys to make sure there haven’t been any big drops in pressure.
It tends to be best to check your tyre pressure ‘cold’. This means before you’ve driven that day, and without any heavy loads in your car. Tyre pressure changes slightly once you’re driving or if you’re carrying passengers, so it’s best to look at the pressure without any external factors that might affect the reading.
Most modern cars are fitted with a tyre pressure monitoring system (TPMS) that should keep an eye on your tyre pressure whilst you’re driving. A light should come on your dashboard if your tyre pressure drops too low when you’re driving. In these cases, you can drive until it’s safe to pull over and then check your tyres to see if you’ve got a puncture.
Your tyre pressure isn’t checked at an MOT, but they will check your TPMS to make sure it’s working properly.
How do I check my car tyre pressure?
Checking your tyre pressure at home with a pressure gauge is quick and easy. Here’s how to check your tyre pressure yourself:
- Take the dust cap off the tyre’s air valve.
- Place the pressure gauge onto the tyre’s air valve and gently push down.
- You should see the needle on the gauge move. When it stops, that’s your tyre pressure.
- Make a note of the pressure, remove the gauge, and replace the dust cap.
- Be sure to check all 4 tyres, as well as your spare tyre (if you have one).
If you don’t have a pressure gauge at home, or you don’t feel confident checking yourself, you can take your car to a local garage and they’ll be able to take a look for you. They might not even charge you.
For more car maintenance guides, you can check out ‘How to stick wing mirror glass back on’ and ‘How to repair scratches on a car’
What pressure should my car tyres be?
Tyre pressure in the UK is generally measured in pounds per square inch (PSI), but it can also be measured in BAR. If you’re trying to work out which one to use, there are plenty of conversion charts online that can help.
Most passenger cars have a recommended tyre pressure of around 31 to 35 PSI when the tyres are cold. This can vary though, particularly if you’re driving a car that’s built to carry a lot of passengers, or something that’s very sporty. It can vary a little depending on what tyres you’re using as well, but usually only if it’s a very specialist car with very specialist tyres.
It’s always best to check your car handbook to make sure you know what your recommended tyre pressure is. Your handbook should give you a general safe PSI boundary to stick to, assuming you’re using the right tyres for your car. If you can’t find your car’s handbook, there are plenty of online tools that’lltell you your recommended tyre pressure based on the make and model of your car.
In any case, tyre pressures under 20 PSI are considered to be a flat tyre, and can be risky to drive on. If you’re on 20 PSI or less, it’s possible you have a puncture and may need to replace or fix the tyre.
If you want to know more about repairing punctures, you can check out our blog ‘Car tyre puncture repair - how long does it take?’
A few final tips…
These are the last few things you need to remember when checking your car’s tyre pressure:
- Keeping an eye on your tyre pressure can be very quick and can save you from potential issues
- Tyres tend to lose about 1 PSI per month, so if your tyres are going down faster than that, you might have a slow puncture
- As well as your car handbook, you might also have a sticker inside one of your car doors showing your tyre pressure boundaries, so it could be worth having a look for that
Urban Jungle is not a financial advisor and information in this article should not be taken as advice or recommendation.
