Tyre Pressure
The Importance Of Correct Tyre Pressure
You should check your tyre pressures monthly, including the spare and before any long distance driving. Make sure the tyre pressures match the pressures recommended by the vehicle manufacturer.
Tyre pressures should if possible be checked cold. If tyre pressures are checked hot, add 4 to 5 psi (0.3 bar) to the recommended pressures.
In the case of unusual pressure loss, the internal and external condition of the tyre should be checked, as well as the condition of the wheel and valve.
How tyre pressure can influence safety
Tyre Life
Driving on under-inflated tyres leads to deterioration and damage of the tyre structure and may ultimately result in rupture and rapid deflation. Even after re-inflation a tyre that has been run under inflated can still rupture.
Aquaplaning
If below the vehicle manufacturers recommended tyre pressure, there is a sharp increase in the risk of aquaplaning.
Braking
A difference of 1 bar, or 14 psi, from the vehicle manufacturers pressure recommendation can increase the braking distance on wet roads by 11 metres. This is more than 2 pedestrian walkways!
Fuel Consumption
Tyres under inflated by 14 psi (1 bar) have increased rolling resistance, which increases fuel consumption by 1 full tank of fuel per year
Maximum grip on the road is vital for road safety. This can only be achieved with the correct pressure in your tyres.
The diagram below shows how much grip a tyre has on the road depending on its pressure.
Under inflated tyres can not only overheat increasing the chances of it bursting, but also lead to poor handling of your vehicle. Low tyre pressure on the front axle will increase under steer (fig. 1) whereas low tyre pressure on the rear axle will increase over steer (fig. 2).
Over inflated and under inflated tyres suffer more damage than those with the correct pressure and need to be changed more often. Even 60% inflation, which is not uncommon, can increase tyre wear and significantly shorten the life of the tyre. Vehicles with under inflated tyres have increased rolling resistance that requires more fuel to maintain the same speed.
Environment
Correct tyre pressure helps to maintain optimum fuel efficiency. This equates to lower CO2 emissions from your vehicle and helps protect the environment.