If you're selling a car, transferring registration, or re-registering a vehicle in Victoria, you'll need a roadworthy certificate (RWC). It's one of those tasks that catches plenty of people off guard — and tyres and wheels are among the most common reasons a car fails its inspection. The good news is that most tyre-related failures are easy to spot ahead of time, and fixing them before the inspection saves you the hassle of a re-test.
What the inspector looks at on your tyres
A roadworthy inspection isn't a full mechanical health check — it's a safety check. When it comes to tyres and wheels, the tester is looking for anything that would make the car unsafe on the road. Here's what gets close attention:
Tread depth
In Victoria, tyres must have at least 1.5 mm of tread across the main grooves of the tyre. That's the legal minimum, but it's worth remembering that wet-weather grip drops off well before a tyre reaches that point. If your tread is sitting near the minimum, expect the inspector to flag it — and consider replacing the tyres regardless, especially heading into wet Geelong winters.
Cuts, cracks and bulges
Inspectors check the sidewalls and tread face for damage: deep cuts, exposed cords, perishing (fine cracks in older rubber) and bulges. A bulge in the sidewall means the internal structure has been damaged — often from hitting a pothole or kerb — and it's an automatic fail because the tyre could let go without warning.
Uneven wear
A tyre worn smooth on one edge but fine everywhere else can still fail if any part of the main tread is below the minimum. Uneven wear also hints at underlying problems — poor wheel alignment, worn suspension components or incorrect pressures — which the inspector may pick up elsewhere in the check.
Matching and suitability
Tyres need to be suitable for the vehicle: the right size, load rating and speed rating for what the manufacturer specifies. Mismatched tyre sizes across the same axle are a problem, as are space-saver spares fitted as a regular wheel. If you've fitted aftermarket wheels, they need to comply with the rules for your vehicle too.
Wheels, nuts and the spare
It's not just the rubber. The inspection covers the wheels themselves — cracked or badly buckled rims, missing wheel nuts, and studs in poor condition can all cause a fail. Wheel bearings with noticeable play often get picked up at the same time. The spare tyre generally isn't held to the same standard as the road wheels, but it's smart to check it anyway; a flat spare won't fail the test, but it won't help you on the highway either.
How to avoid a failed inspection
- Do a walk-around first. Check tread depth with a gauge or the built-in wear indicators, and run your hand over each tyre feeling for bulges or exposed cords.
- Check all four tyres, inside edge included. Inner-edge wear from alignment issues is easy to miss because you can't see it from standing height.
- Sort obvious issues before booking. If one tyre is clearly on its way out, replacing it beforehand is cheaper and quicker than failing, fixing and re-testing.
- Fix the cause, not just the symptom. If a tyre wore out unevenly, get the alignment checked when the new one goes on — otherwise the replacement will wear the same way.
A certificate, not a guarantee
One last thing worth knowing: an RWC confirms the car was safe on the day of inspection — it isn't a warranty of overall condition. If you're buying a car with a fresh certificate, it still pays to look at the tyres yourself. Plenty of cars pass with tyres that are legal but close to the end of their life, which means a new set may be on the cards sooner than you'd like.
If you're getting a car ready for sale or transfer around Geelong, the team at Global Tyres Geelong in North Geelong can look over your tyres and wheels, check your alignment and fit replacements if needed — so your car turns up to its roadworthy inspection with nothing to worry about.