Tyre pressures - should they be increased for driving at speed?

I have read with interest your recommendation that tyre pressures be dropped by 3psi for comfort. Yet I remember when you recommended that for long distance, high speed, well loaded travel in a hot climate they should be increased by 3psi. Is this still the case please?

Asked on 9 August 2016 by lilley

Answered by Honest John
As soon as you drive any distance over 20 miles the tyres heat up and that alone increases the pressure in them by 3-4psi. But obviously if carrying a heavy weight of passengers and luggage you need to allow for that by a further increase in pressure.
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