How to Check Your Tyre Pressure (And Why It Matters)

Tyre pressure is the single most overlooked bit of routine maintenance on a car. It takes two minutes to check, yet most drivers only think about it when a warning light appears or the handling starts to feel odd. The trouble is, by then the tyre has often already been damaged.

Why pressure matters

An under-inflated tyre bulges at the bottom and rolls on its shoulders, which wears the edges of the tread long before the centre. It also runs hotter, increases rolling resistance — so you use more fuel — and is significantly more likely to suffer a blowout at speed. An over-inflated tyre wears the centre of the tread and gives a harsher ride with less grip.

• Under-inflation: edge wear, higher fuel use, hotter running, blowout risk.
• Over-inflation: centre wear, harsh ride, reduced contact patch and grip.
• Correct pressure: even wear, best economy, shortest braking distance.

Finding the right pressure

The correct pressure is not a guess. It is printed on a sticker inside the fuel filler flap or the driver’s door shut, and it is in the handbook. There are usually two figures — one for a lightly loaded car and a higher one for a full load. Use the figure that matches how the car is being used.

Checking it properly

• Check pressures cold — before driving, or at least three hours after.
• Use a reliable gauge; air-line gauges at forecourts vary wildly.
• Check all four tyres, and the spare if you carry one.
• Reset the tyre-pressure monitoring system after adjusting, if your car has one.

A monthly two-minute check is the cheapest tyre insurance you can buy.

If a tyre will not hold its pressure between checks, it has a slow puncture or a leaking valve — and that will not fix itself. Send an enquiry from the home page or call 07778 496767 and we will come and look at it before it becomes a roadside failure.

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