Tyre Pressure Guide: What PSI Should Your Tyres Be?
- Dan Rankin
- Feb 5
- 5 min read
Tyre pressure is one of those things most people only think about when the warning light comes on — or when a tyre goes flat. But running your tyres at the wrong pressure affects everything from fuel economy to handling to how long your tyres last. The good news? Checking and adjusting tyre pressure takes about five minutes and costs nothing.
Here's how to find the right PSI for your car, how to check it properly, and what happens when you get it wrong.
🔍 Why Tyre Pressure Matters More Than You Think
Your tyres are the only part of your car that actually touches the road. When the pressure is wrong, everything else has to compensate.
Underinflated tyres flex more than they should. That extra flex generates heat, wears the outer edges of the tread faster, and makes the engine work harder to move the car. Fuel economy drops, stopping distances increase, and the tyre wears out well before its time.
Overinflated tyres have the opposite problem — less contact with the road means less grip, a harsher ride, and wear concentrated in the centre of the tread. In wet conditions, overinflated tyres are more prone to losing traction.
The difference between correct pressure and 20% under can mean 5–10% worse fuel economy and thousands of kilometres less tyre life. Over the life of a set of tyres, that adds up to real money.
📋 How to Find the Correct Tyre Pressure for Your Car
The right tyre pressure for your car isn't printed on the tyre itself — that number is the maximum pressure the tyre can handle, not what you should run it at.
The Tyre Placard
Every car has a tyre placard that lists the manufacturer's recommended pressures. You'll usually find it in one of these spots:
Inside the driver's door frame (most common)
Inside the fuel filler cap
In the glovebox
In the owner's manual
The placard shows the recommended PSI for front and rear tyres, and often includes different pressures for light loads versus full loads or highway driving.
Front vs Rear Pressures
Many cars specify different pressures front and rear. Front-wheel-drive cars often run slightly higher pressure up front where the engine weight sits. Follow what the placard says rather than running the same pressure all round.
When to Adjust
If you're loading the car up — roof box, boot full of gear, towing a trailer — check the placard for the "full load" recommendation. It's usually 4–6 PSI higher than the standard setting.
⚙️ How to Check Your Tyre Pressure Properly
Checking tyre pressure is straightforward, but there are a few things that affect accuracy.
Check When Cold
Tyres heat up as you drive, and hot air expands. If you check pressure after a long drive, you'll get a reading 4–6 PSI higher than the true cold pressure. Check first thing in the morning, or after the car has been parked for at least three hours.
Use a Reliable Gauge
Service station gauges cop a hiding and aren't always accurate. A decent digital tyre pressure gauge costs $20–$40 and lives in your glovebox. Worth it for consistent readings.
Don't Forget the Spare
If you've got a full-size spare, it should be at the same pressure as your other tyres. Temporary spares (space savers) usually need to be at 60 PSI — check the label on the tyre.
How Often to Check
Once a month is the general recommendation. Tyres naturally lose 1–2 PSI per month even without a puncture, so regular checks keep you in the right range.
⚠️ Signs Your Tyre Pressure Is Wrong
Your car will usually tell you when something's off — you just need to know what to look for.
Underinflation Signs
Car feels sluggish or heavy to steer
Fuel economy drops noticeably
Tyres look visibly flatter (though this can be hard to spot until they're very low)
Uneven wear on the outer edges of the tread
Overinflation Signs
Harsh, bumpy ride — you feel every imperfection in the road
Car feels twitchy or nervous, especially in corners
Wear concentrated in the centre of the tread
Tyres feel rock-hard when you press on the sidewall
TPMS Warning Light
Most cars built after 2014 have a tyre pressure monitoring system (TPMS). If the light comes on, don't ignore it — check all four tyres (and the spare if your system monitors it). The light triggers when pressure drops about 25% below recommended, which is already low enough to cause problems.
If you're seeing uneven wear patterns, a wheel alignment check is worth doing alongside the pressure correction.
📍 Tyre Pressure Checks in North-East Victoria
Ynot Auto offers free tyre pressure checks at our Benalla workshop — home to our Goodyear tyre store. We'll also check tread depth and condition while we're at it.
If your tyres are wearing unevenly or you're not sure what pressure you should be running, drop in or book a service and we'll sort it out.
❓ Frequently Asked Questions
What PSI should my tyres be?
Check your car's tyre placard — usually inside the driver's door frame. Most passenger cars run between 30–36 PSI, but it varies by vehicle and load. The number on the tyre sidewall is the maximum, not the target.
Can I use the pressure written on the tyre?
No. The number moulded into the tyre sidewall (e.g., "Max 50 PSI") is the maximum safe pressure for that tyre, not the recommended running pressure for your car. Always use the placard figure.
How often should I check tyre pressure?
Once a month is ideal. Tyres lose 1–2 PSI naturally over time, and temperature changes affect pressure too — tyres lose about 1 PSI for every 10°C drop in temperature.
Does tyre pressure affect fuel economy?
Yes, significantly. Underinflated tyres increase rolling resistance, which makes your engine work harder. Running 20% below recommended pressure can cost you 5–10% in fuel economy.
Should I inflate to a higher pressure for highway driving?
Some manufacturers recommend a slightly higher pressure for sustained highway speeds or heavy loads — check your tyre placard. If it doesn't specify, stick to the standard recommendation.
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