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Use the right tyre pressure

There are lots of good reasons to make sure your tyres are always inflated to the correct pressure. It will save you fuel - which is better for the environment and your wallet - and it’s also safer.


Be safe - check your tyre pressure

Kiwis aren’t good at regularly checking tyre pressure. An AA tyre pressure survey conducted on 150 vehicles getting a warrant of fitness check at an AA Inspection Centre in early 2010, found that 48% had underinflated tyres.

Air pressure to use

Your tyres should be kept at the pressure recommended by your vehicle’s manufacturer.

Information about the correct pressure for your tyres can be found on a label inside the driver’s door pillar (or passenger side in some makes) or in your owner’s manual.

There are two measurements used for air pressure – kPa (kilopascal) and psi (pounds per square inch). The label in your car and information in your vehicle manual should have the recommended pressure in both measurements and air pumps at service stations should also display both readings.

Did you know?
You can find your recommended tyre pressure on a label inside the drivers’ door pillar or listed in the owner’s manual.

When you change tyres, your mechanic should make sure the new tyres meet the manufacturer’s specifications. If your wheels or tyres are similar to the manufacturer’s specifications, then the manufacturer’s tyre pressure recommendation should suffice.

Wheels or tyres that are several sizes different to the manufacturer’s recommendations can change the suspension geometry and make the car unsafe. Interference with brakes, suspension and body work can also happen, so seek expert advice before moving outside manufacturer’s wheel size recommendations.

Correctly inflated tyres are safer

Your tyres are the only thing that’s keeping your vehicle gripped to the road.

It’s very important you have good quality tyres with adequate tread; they meet the manufacturer’s specifications and are pumped up to the recommended pressure. This will help your vehicle performs to the best of its ability and therefore help to keep you safe.

Overinflated tyres wear unevenly, have less grip on the road and can affect braking ability.

Underinflated tyres wear more quickly and affect cornering, braking and water dispersion.

Correctly inflated tyres save fuel

Imagine riding a bicycle with flat tyres. The effort you need to get it moving is far greater than if the tyres are properly pumped up.

The same principle applies to motorised vehicles. In early 2010 we proved this in a test conducted on common fuel consumption theories. Our fuel myths test found that driving a car with tyres 7 psi underinflated increased fuel consumption by nearly 8%.

Check tyre pressure monthly

We recommend you check your tyre pressure at least monthly or whenever you’re going on a long trip or carrying heavy loads. Try to get into the habit of checking pressures whenever you’re at a service station.

If you’re not sure how to use the service station’s air pressure system, ask a staff member at the service station to show you.

You can also buy tyre pressure gauges from motor accessory shops, but make sure you buy a good quality one.


More information

How to change a car tyre

Click to learn more