Fuzz Townshend explains the science of tyre pressure and why it matters
6th June 2025
Your vehicle’s tyres are its most important attributes, full stop. So paying attention to their condition and their pressures is critical.
Allowing the standards to slip in these areas of vehicle maintenance might see you spinning horribly out of control – even on the driest of roads – hurtling towards an oncoming speeding vehicle, and that’s just on a humble 40mph ‘A’ road.
The same goes for the frightening motorway tyre blow out, when control vanishes in an instant, and utter panic ensues. Of course, such dreadful life scenes may be avoided by a simple, frequent routine that takes but a few minutes to complete…
Check your tyres
Get down and check your tyres’ physical conditions and their pressures, including any spare carried.
It is a legal obligation that a vehicle’s tyres meet minimum requirements regarding tread depth and overall condition. The latter can be taken to include pressure settings.
Of course, many modern vehicles feature ‘Tyre Pressure Monitoring Systems’ (TPMS), which keep an electronic ‘eye’ on the relative rolling radii of wheel and tyre assemblies, but these are not foolproof, and they certainly don’t detect all impending physical failures, which is why visual and inflation checks are so very important.
Too high
If your vehicle’s tyre pressures are set too high, the ride will be harder. Not only that, but the tyre will wear prematurely in the middle section of its tread, due to the domed ballooning of the tyre. It will also offer a smaller contact area between itself and the road surface, which increases the possibility of skidding, resulting in a loss of vehicle control.
Too low
Ah, now here are where horror stories of ripped and shredded carcasses littering the land may be told. These tales are real.
The carcasses are those of under-inflated tyres that have dramatically disintegrated, dropping metal wheels to the road surface to grind alarmingly to destruction, and they can be found every few metres along busy roadways. I will stick my neck out and suggest that most of these losses are due to user neglect, and so may be largely avoidable.
When a tyre is under-inflated, its internal air pressure is too low, so its walls can no longer support the weight of the vehicle. The tyre is ‘squashed’ at its base, which when driving is constantly changing as the wheel rotates. The ‘squashed’ tyre walls flex and distort more, sometimes even rubbing internally, building up large amounts of heat and compromising the construction materials. As this occurs, it will also lead to interesting, vague or uncontrollable handling characteristics.
As the vehicle continues to travel at speed, the situation can escalate very quickly and lead to a disintegrated tyre, putting both the driver and potentially other road users in danger.
Do… Check your vehicle’s tyre pressures often, at least monthly.
Don’t… Leave it until it’s too late!
For more information on how to check your tyre pressures, visit this blog, or contact your local Landsail dealer.
