The effects of overinflated tyre pressure

Overinflated tyres are just as risky as underinflated tyres. With too much air, you’re in danger of accidents, poor vehicle handling, and extra costs caused by excess tyre wear. So, checking tyre air pressure is crucial to ensure your tyres last and that you stay safe on the road.

In this guide, we’ll explain everything you need to know about overinflated tyres, including how to check air pressure, the effects on the road, and, when you should increase tyre pressure.

If a tyre is overinflated, there are tell-tale signs to look for. Often, an overinflated tyre wears more prominently in the middle. This is because too much air can cause the tread to bulge in the centre, forcing more contact with the road. As a result, the centre of the tyre will wear away excessively. You may also notice that your vehicle has poor traction or that driving feels bumpy, even on a smooth road.

To check if your tyres are overinflated, give them a visual once-over first. Then, refer to your vehicle handbook or manual to see the recommended tyre pressures. Usually, you can find this in the glove box or passenger door. If you’re in a newer car, it may display maximum and recommended PSI levels (the unit used to measure air pressure within your tyres) on your dashboard. And it may even tell you the PSI for each tyre, so you know which one is causing issues.

Although it might be tempting to pump more air into your tyres to save you from inflating them again too soon, it’s hazardous. Overinflated tyres come with substantial safety risks, not just for you and your vehicle but for other drivers on the road.

Overinflated tyres cause tyre tread to wear away more quickly, especially in the centre. While the outer edges of your tyre may look perfect, the centre could have almost no tread. Uneven wear means you’ll need to replace tyres more frequently, resulting in unnecessary extra costs.

A reduction in tyre tread can also lead to lower traction. As a result, you may experience poor vehicle handling as there’s less contact with the road. This also means your braking threshold will be much higher because of reduced grip.

Overinflated tyres are stiffer and less flexible, which makes them more susceptible to damage from potholes, kerbs, and other road debris. This also affects vehicle suspension because the tyres cannot absorb impact from bumps in the road. Aside from an increased risk of punctures, it also means a less comfortable drive.

If tyre pressure is uneven, it’ll make your vehicle less stable. This is terrible for driving performance and for the safety of others because it dramatically increases the risk of blowouts and accidents.

If you think your tyres could be overinflated, it’s often an easy fix—as long as there’s no severe damage. For instance, if the tyre tread is already worn down in the middle, you should head to a garage to get a new tyre fitted. While removing air will lower risks slightly, reduced tread is dangerous and can lead to accidents.

However, if there’s no apparent damage, go to a local petrol station to use the air pressure machine. These machines usually have two parts—one to inflate air, and one to release air. Attach the nozzle to your tyre and allow it to remove air from the tyre. It’s essential to use the specific machine as it lets air out slowly and safely rather than all in one go. The latter could cause even more damage.

Unless your dashboard shows you which tyre is overinflated, ensure you check all four. It might be difficult to know from a simple visual check, so it’s best to be thorough and assess the PSI of each tyre. If you’re unsure, read up on how to check your tyre pressures first.

Although overinflated tyres are dangerous for day-to-day driving, there are occasions when you need additional air. Generally, you’ll only need to overinflate tyres, or increase pressure above normal value when carrying extra loads, such as heavy luggage or trailers and caravans. Since your vehicle is carrying extra weight, additional pressure can help power the car and stop your tyres from excess wear.

Usually, you can find the recommended PSI for heavy loads in your vehicle handbook. If you’re unsure, check online. Remember, the PSI should be returned to the recommended level after removing the extra weight. Otherwise, your tyres will be at risk.

Underinflated tyres are just as dangerous. It’s tempting to ignore the flashing amber warning light—but it’s not a good idea. Tyres with low air pressure will wear away at the edges and damage more quickly, increasing your risk of punctures.

Lack of air makes tyres heavier, which adds further rolling resistance when driving. This impacts braking performance and increases fuel consumption as the engine has to exert more power to move the wheels around. So, checking your tyre pressures often to ensure they have enough air is critical—for vehicle performance and maximising road safety for you and other drivers.