Your tyres are the only part of the vehicle touching the road: four patches, each about the size of your palm. Wrong pressures ruin grip, braking and fuel economy and wear tyres out early; worn or aged tyres are dangerous in the wet. A monthly check takes ten minutes.
You'll need
- A tyre pressure gauge (don't rely only on the petrol-station gauge — they're often inaccurate)
- Access to an air pump or compressor
- A coin or a tread-depth gauge
Step by step
- 1
Find the correct pressures
Look for the tyre-pressure sticker in the driver's door frame, inside the fuel flap, or in the owner's manual. It gives front and rear pressures, sometimes with a higher figure for a fully loaded car. Ignore the number moulded on the tyre wall — that's the tyre's maximum, not your car's setting.
- 2
Check the tyres cold
Check before driving, or after no more than 2–3 km. Tyres heat up and pressure rises as you drive, so a hot reading will look higher than it really is.
- 3
Measure each tyre
Unscrew the valve cap, press the gauge firmly and squarely onto the valve until the hissing stops, and read it. Note the unit — PSI or bar (1 bar is roughly 14.5 PSI).
- 4
Adjust
Add air in short bursts and recheck until you reach the figure on the sticker. If a tyre is over-inflated, press the pin in the centre of the valve briefly to let air out. Refit every valve cap — they keep dirt out of the valve.
- 5
Check the tread depth
Look into the main grooves for tread-wear indicators: small raised bars across the bottom of the groove. When the tread is worn level with them (about 1.6 mm), the tyre must be replaced. For good grip in heavy rain, replacing at around 3 mm is a far safer point.
- 6
Look for damage and uneven wear
Run your eyes (and a gloved hand) around the tread and both sidewalls. Bulges, cuts, exposed cords or embedded objects mean the tyre needs attention now. Wear on only the inner or outer edge usually points to wheel alignment problems; wear on both edges suggests under-inflation; wear in the centre suggests over-inflation.
- 7
Check the tyre's age
Find the DOT code on the sidewall; its last four digits are the week and year of manufacture (for example 2321 means week 23 of 2021). Rubber hardens with age and heat, even when it's never used. Most tyre makers advise replacing tyres around 6 years old whatever the tread looks like, so be wary of 'new' tyres that have been in storage for years.
- 8
Don't forget the spare
Check the spare's pressure at the same time. A space-saver spare often needs a much higher pressure than your normal tyres — it's marked on the wheel.
Pro tips
- Check once a month and before long trips; potholes and speed bumps can knock a tyre down faster than you'd expect.
- Motorbikes: pressures matter even more on two wheels. The figures are usually on a sticker on the swingarm or chain guard, or in the manual.
- Tyres on the same axle should match in size, type and, ideally, wear.
Stop and get a mechanic if…
- A tyre keeps losing pressure (a slow puncture or a leaking valve or rim).
- Any bulge or cut in the sidewall — sidewall damage can't be safely repaired.
- The car pulls to one side or the steering wheel vibrates at speed.
General guidance only. Your owner's manual has the final word on specs, fluids and procedures for your vehicle. Last reviewed 24 September 2026.