Tyre Pressure changes with the rise in temperature. Rubber and air expands and contracts depending on the heat. An under-inflated tyre leads to excessive sidewall flexing thereby generating excessive heat which will eventually lead to faster wear & premature failure. An over-inflated tyre, on the other hand, can cause excessive wear and tear to the center of tread and in extreme case it can cause the tyre to burst. Overinflated tyres will also reduce ride comfort. The key is to monitor tyre pressure (including the spare) regularly. For the most accurate reading, check the pressure when the tyres are cold or have not travelled for more than 3 hours. Inflate the tyres to the recommended settings often found on the driver’s door jamb and/or the vehicle owner’s manual.