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I understand it is preferable to check tyre pressures when the tyres are cold.

When the tyres on my vehicle are warm they seem to increase a couple of psi. The recommended pressure is 36psi however after driving they increase to 38psi.

I guess this increase is of little concern and I should ensure that the tyre pressures are at the recommended psi when cold, correct ?

Daniel

From the "Ask Jack" archives - 23 November, 2010

The important point is you are actually checking your tyre pressures. A recent survey carried out by the AA suggested at least half the cars on our roads have underinflated tyres.

With regards to the difference in pressure hot to cold; I would not be overly worried.

The recommended pressure is when the tyre is cold however the interpretation of cold can vary from one owner to another.

In general inflating to the cold pressure would be perfectly acceptable for the average motorist.

You need to take into account inaccuracies with the various tyre gauges that are being used at service stations around the country so a 2psi difference is really insignificant for the average passenger car.