Tyre Pressure: Over Inflation and Under Inflation

Tyre pressure: over inflation and under inflation, why does it matter?

At Bud’s Tyres we often are replacing tyres where customers have neglected the tyre pressure without realising its importance or have been given the wrong information. We are here to help you stay safe and keep your set of tyres on the road for longer.

Unfortunately, it is common that we give ourselves a pat on the back for remembering to check the engine oil and thats about as far as vehicle maintenance goes. Tyre pressure, along with other tyre maintenance, should definitely be on that to-do list. You should be checking tyre pressure at least once a month.

What is Tyre Pressure?

Tyre pressure indicates the amount of air inside of a tyre. Each make and model requires a unique pressure. You can find this on your tyre place card, owners manual or by following a tyre pressure chart online. Failure to check tyre pressure will often result in uneven wear, poor vehicle control and potential tyre failure. There are a number of situations that determine if tyre pressure should be altered such as beach driving or heavy loads on light trucks. You can find your recommended tyre pressure here.

How to Check Tyre Pressure?

Tyre pressure should be monitored frequently so it may be beneficial to set a repeat reminder or push notification in your phone or set a time where you will check for this, such as every time you fill up at the petrol station. You must know the correct pressure for your vehicle before checking so you know what to look for. If your tyres and driving control feels abnormal it could be an indication your tyre pressure is incorrect and you should check it to address the issue or rule out the problem.

1. Check the tyre place card, owners manual or look for any internal car stickers to find out the required tyre pressure (PSI). If you can’t find these you can always find this information online. Keep in mind that front and rear tyres could require different pressure levels.
2. Unscrew the cap on the air valve and check tyre pressure with tyre pressure gauge by pushing it firmly in. If you don’t have a tyre pressure gauge you can find one at your local petrol station.
3. Attach the air hose and fill to the manufacture recommended PSI.
4. Recheck with gauge and screw cap back on. Release air if the reading is too high.

When to Check Tyre Pressure?

Realistically, most individuals will only get around to checking tyre pressure monthly. We do suggest that this is appropriate however, you made need to be a bit more proactive depending on your vehicle and driving requirements. Checking every week or fortnight is ideal. The more you can check the better in prolonging the life of your tyre and the benefit of considering safety measures. Abnormal leaks or an accelerated loss of pressure is why it may be a good idea to check more often than a month.

Along with monitoring tyre pressure you should also check the tyre sidewall for any punctures or damage that could rapidly fasten the release of air from the tyre.

Tyre Pressure Guide

*Please not this is just a general range not specific to tyre size

Passenger Vehicle: 30 – 36 PSI

Sports Vehicle: 32 – 50 PSI (Small – Large Vehicle Range)

4WD: 32 – 38 PSI (Bitumen)

22 – 28 PSI (Mud)

22 – 28 PSI (Rocky Terrain)

18 – 26 PSI (Sand)

Light Truck: 40 – 45 PSI

Over Inflation

Expect a harsh, uncomfortable and bouncy ride. It is more common than you think to over-inflate tyres so you can get away with not checking tyre pressure for longer. This is extremely damaging to your tyre and is highly unsafe. If tyres are overinflated by just a little it can cause irreversible damage and uneven wear.

Properly Inflated

Your passenger tyre should be inflated within the manufacturers guidelines at all times. When driving a 4WD or sports vehicle your PSI may need to be adjusted to reflect your driving conditions. By correctly monitoring tyre pressure and inflating tyres accordingly even wear and a smooth drive is expected.

Under Inflation

Underinflation causes tyre wear on the outer surface of the tyre by generating too much friction as you travel. It is far too common to drive under the manufactures recommendations. Underinflation can cause handling problems, a blowout/ loss of control, weakened fuel economy, increased rolling resistance, reduced load capacity, exposure to punctures and the reduced life of your tyre’s tread.

4WD and Beach Driving

4X4 vehicles should follow the manufacturers guidelines unless driving through rugged terrain although this should only be done with knowledge of the long term damage this could cause to your tyres and vehicle. Off-road driving often sees the tyre pressure lowered in order to drive over the unexpected or unusual such as rocks or sand. It may be beneficial to lower tyre pressure across different terrains and re-inflated once reintroduced to regular road conditions.

Tyre pressure: over inflation and under inflation, why does it matter?