Tyre Pressure Guide: What PSI Should Your Car Tyres Be?

By Jim's Mobile

Just ordered a set of new tyres but you’re not sure about tyre pressure? Read on for easy-to-understand info on how to get the right tyre pressure, and why it matters.

Having the wrong tyre pressure can lead to accelerated tyre wear and premature tyre replacement. Since tyres come at a cost, it’s critical to ensure you get the most out of your purchase when you buy new tyres, so maintaining correct tyre pressure is a key task when it comes to extending the life of your tyres. However, inflating our tyres to ensure they are at their ideal tyre pressure is a task many of us neglect. This is why Jim’s Mobile Tyres have created this helpful car tyre pressure guide.

What is Car Tyre Pressure?

Tyre pressure is the measurement of the amount of air in a tyre, and is measured in Pounds per Square Inch (PSI).

If you’re wondering, “What PSI should my tyres be?”, the answer isn’t the same for every vehicle. Recommended car tyre pressure in PSI varies according to vehicle make and model, and tyre type, with car manufacturers carefully designing and testing tyres to maximise safety and efficiency. They specify optimal tyre pressures according to various driving circumstances.

Ideal tyre pressure also varies depending on the surfaces you drive on, speeds you travel at, distances you cover, and weight your vehicle carries or tows.

Why Correct Tyre Pressure Matters More Than You Think

What do car tyres ultimately do? Tyres cushion your vehicle’s weight and provide grip so that you can steer, brake, and drive safely on the road. But they only work effectively if they’re correctly inflated.

Proper tyre inflation allows tyres to perform as designed by maintaining optimal contact with the road, improving grip and ride comfort, and allowing for wheels to roll smoothly (which reduces fuel consumption). Correct tyre inflation will reduce early tread loss, and save you money on premature tyre replacement. It will also help to ensure a safer drive.

The Risks of Incorrectly Inflated Tyres

When you have the wrong tyre pressure for your driving needs, you may deal with the following adverse effects:

1. Increased fuel consumption: If your tyres are under-inflated, there’ll be greater rolling resistance on the road, which makes the engine work harder and increases fuel use.

2. Uneven tyre wear: When tyres are over or under-inflated, they wear more in certain areas than others. On standard bitumen roads:

3. Safety risks: Incorrect tyre inflation can lead to safety risks, including:

Tyre blowouts and punctures
Increased braking distance. (The surface area of over-inflated tyres is reduced, and hence the tyre doesn’t grip to the road as it should. It takes longer for the vehicle to stop, which could increase the risk of impacts.)
Aquaplaning, where tyres lose contact with the road entirely (occurs on wet roads).

4. Reduced tyre lifespan: Incorrect tyre pressure is one of the most common reasons why you might need a tyre replacement earlier than expected. Tyres wear faster when you don’t have appropriate tyre pressure. Incorrect pressure can also increase the risk of tyre failure in the form of damage and blowouts. As quality tyres rarely come cheap, it’s important to maintain your tyres so they last as long as possible, and maintaining air pressure is a crucial part of tyre maintenance.

What is the Recommended Tyre Pressure for Cars in Australia?

Ensuring you have correct tyre pressure is crucial for driving safety, tyre longevity, and fuel economy. What’s the normal car tyre pressure in Australia? Recommended pressure varies based on tyre, vehicle type, driving surfaces and load. In saying that, there are some general PSI ranges.

Typical PSI Ranges

For driving on paved roads in Australia, the standard PSI:

30-35 PSI for passenger vehicles
32-38 PSI for 4WDs, SUVs and light commercial vehicles.

When driving in different circumstances, consider the following tyre pressure adjustments:

Driving off-road (mud, gravel, uneven surfaces): Reduce pressure between 2-4 PSI below the standard recommended pressure for your vehicle. This will improve traction on unsealed roads, allow the tyre to flex and keep contact with the road surface. It will also minimise the risk of tyre damage on rocky surfaces. (Note, avoid going too low, as insufficient pressure can result in sidewall damage and/or tyre ”pinching”.)

Towing or driving with a heavy load: Increase tyre pressure by 2–5 PSI above the recommended tyre pressure for your vehicle. This will provide extra support for the weight you’re carrying/towing, and help ensure there’s full tyre contact. (Check your vehicle owner’s manual for specific recommended PSI according to varying loads.)

Driving on Freeways for Long Duration: Retain standard recommended tyre pressure.

Important Notes on Adjusting Tyre Pressure:

Follow the PSI recommended by your vehicle’s manufacturer for your driving conditions and load, rather than general PSI ranges.

The PSI listed on the tyre itself shows you the maximum PSI the tyre can be inflated to, rather than the optimal PSI for your vehicle. It’s an important pressure to be aware of, but you only need to be mindful of not exceeding it. Follow, instead, the vehicle’s recommended PSI. (See below the section on finding recommended PSI.)

If you adjusted tyre pressure for driving off-road or for carrying loads, remember to readjust to the standard recommended PSI once you resume driving on sealed roads.

Where to Find Correct PSI

You can find the recommended PSI for front and rear tyres in the following places:

In your vehicle owner’s manual
On the sticker inside the driver’s door frame
Sometimes on the fuel filler flap.

How Incorrect Tyre Pressure Affects Tyre Wear

A leading cause of uneven tyre wear is incorrect tyre inflation. When the air pressure is wrong, tyres don’t function as they should. They don’t sit flat on the road, meaning that parts of the tread will wear faster than others.

Over-inflated tyres wear down in the middle. This centre tread wear reduces grip and your tyres will have a shortened lifespan.

Under-inflated tyres flex too much and roll out onto their edges. This results in shoulder wear as well as a build up of heat in the tyre, which degrades the tyre. Again, the tyre deteriorates faster than it otherwise would.

Incorrect tyre pressure will reduce tyre life and invite the need for early tyre replacement. So if you don’t pump your tyres correctly, you’ll likely need to buy new tyres sooner than expected.

When a Tyre Pressure Problem is Really a Tyre Replacement Issue

Are your tyres losing air, despite you regularly topping them up? It’s most likely a problem with the tyre itself. Common warning signs of a failing tyre include:

Regular pressure leaks
Deformities or bulges in the tyre sidewall
Cracks in the tyre rubber
Tread depth that’s uneven, and can’t be corrected with tyre pressure adjustment.

What to do: Your tyre might be compromised and replacing air won’t solve the problem. A tyre repair may be viable, but if you’ve already tried that and the problem is still occurring, you likely need to buy new tyres. If you’re not certain, chat to a tyre expert about getting new tyres, rather than continuing with patch up jobs.

Buying New Tyres? We Bring the Tyre Shop to You

Where do I find the best tyres for my car at reasonable prices?

When you need to buy tyres, we make it easy. Rather than you heading to a tyre store on poorly-functioning tyres, Jim’s Mobile Tyres comes to you with new tyres! We specialise in new tyre sales, as well as new tyre fitting, amongst our many services. Your new tyres are professionally installed, set to the correct pressure, and your old tyres are removed and disposed of.

Looking to buy tyres for your car? We’ll help you choose the right ones and fit them at your home or work. We have great relationships with tyre manufacturers and sell top-tier tyres at competitive prices. Want a popular brand tyre, or something more unique? Our range of quality tyres for different vehicle types is wide, so there is certainly a durable tyre for your needs.