Whatever tyres are fitted to the towing car, caravan, trailer tent or motorhome, it is essential to the safety and stability of the combination that all tyres are correctly inflated for the applied load. Tyres that are under-inflated are much more likely to suffer from a blowout which can cause loss of control of the vehicle. Any debris left on the carriageway will prove hazardous for other motorists and fitting of a replacement tyre on the hard shoulder of a motorway is a notoriously dangerous activity.

Keeping tyres correctly inflated ensures an even wear rate leading to longer tyre life. Under-inflated tyres places excess loads on the outer edges of the tyre, causing the shoulders to wear more rapidly. Over-inflated tyres will experience higher wear rates in the centre of the tread.

Fuel costs can also be minimised by ensuring tyres are correctly inflated. When tyres run under-inflated their rolling resistance, or the force needed to make them turn, increases. This means that the engine has to work harder and more fuel is used, making the vehicle less economical.

Pressures should be checked and adjusted when the tyres are cold before every journey. Never reduce pressures when the tyres are warm as they could then be too low when they cool down. After checking the pressure, ensure the valve is not leaking and a valve cap is fitted to each tyre.

The correct inflation pressures for your car tyres can be found in the vehicle handbook, inside the fuel filler cap or on a plate located on the driver’s door sill. In the absence of special towing recommendations, the rear tyres of cars should be set at the ‘fully laden’ pressure. Where full load pressure does not differ from that for normal driving , the rear tyre pressures should be increased by 4 to 7 psi (0.3 to 0.5 bar).

Appropriate inflation pressures for the actual load imposed on caravan and trailer tent tyres can be found by clicking Load and inflation tables. Special conditions apply to Self Supporting Run Flat Tyres where they are fitted to the towing vehicle. Guidelines for tyre pressures and conditions of operating in a run flat condition are given in the vehicle manufacturer’s handbook.