Best Car Inspection Tools for Used Cars in Australia
Buying a used car is a gamble. A shiny exterior can hide a tired engine, crash repairs, or worn-out tires. One bad buy can cost you thousands. The good news? You can flip the odds in your favor. With the right tools for a used car inspection, you can check any car like a pro. You do not need to be a mechanic. You just need to know what to bring and what to look for.
That is exactly what this guide gives you. We cover the best car inspection tools for used cars in Australia, what each one finds, and how to use it. No jargon. No guesswork. Just a simple, proven kit that helps you spot trouble early, negotiate harder, and drive away with confidence.
Why a Toolkit Beats a Test Drive
A test drive tells you how a car feels. It does not tell you what is wrong underneath. Sellers can hide a lot. A warning light gets cleared. A leak gets cleaned up. Fresh paint covers old damage.
Tools reveal what a quick look cannot. They turn guesswork into evidence. That evidence gives you power to negotiate or walk away.
The Three Tools You Cannot Skip
Start here. These three tools catch most of the expensive problems.
| Tool | What it finds | Rough cost (AUD) |
| OBD2 scanner | Hidden engine and sensor faults | $30 to $150 |
| Tyre tread depth gauge | Worn or unevenly worn tyres | $5 to $20 |
| Paint thickness gauge | Crash repairs and resprays | $40 to $120 |
Buy these first. They pay for themselves the moment they stop one bad purchase.
OBD2 Scanner
This is your most powerful tool. It reads the car’s onboard computer. Plug it into the port under the dashboard. It shows stored fault codes in seconds. Here is why it matters. A seller can clear the dashboard light before you arrive. A scanner still shows pending codes and recent faults.
It can flag misfires, sensor failures, and emissions problems. Advanced scanners also read ABS, airbag, and transmission systems. Pick a trusted brand. Cheap knock-offs can misread data. Check it works with the make and model first.
Tyre Tread Depth Gauge
Tires are costly. A full set can cost hundreds of dollars. A tread gauge gives an exact reading in millimeters. In Australia, the legal minimum is 1.5mm. Anything near that means replacement is due soon.
Look at the wear pattern too. It tells a story.
| Wear pattern | Likely cause |
| Worn on one edge | Wheel alignment issue |
| Worn in the centre | Over-inflation |
| Patchy or bald spots | Balancing or braking problem |
Check every tire. Do not trust a quick glance.
Paint Thickness Gauge

A paint thickness gauge is one of the most useful tools for a used car inspection. It uncovers hidden crash damage by measuring the paint and filler on each panel. Hold it to the metal. Read the number. Repeat on every panel. Factory paint is consistent. One panel that reads much thicker has likely been resprayed or filled. A repair is not always a deal-breaker. But it should be disclosed. And it gives you room to negotiate.
Tip: inspect in daylight. Natural light reveals overspray, color mismatches, and uneven panel gaps.
Block Tester
A block tester checks for a blown head gasket. That is one of the most expensive faults a car can hide. It detects combustion gases in the cooling system. The test takes minutes.
Follow these steps:
- Let the engine cool slightly.
- Draw air from the radiator or coolant tank through the test fluid.
- Watch the color.
Blue fluid that turns yellow means combustion gases are present. That points to head gasket failure. Walk away or renegotiate.
Torch and Inspection Mirror
The worst problems hide where you cannot see. A bright torch and a telescopic mirror fix that. Use them to check under the car and inside the wheel arches.
Look for:
- Oil and coolant leaks
- Rust on the chassis rails
- Fresh undercoating that hides corrosion
- Signs of welding or repair
Damp patches and rust bubbles are easy to miss in poor light. Good light finds them fast.
Magnet for Filler Detection
A small magnet is one of the simplest tools for a used car inspection. It is cheap, clever, and backs up your paint gauge. Run it over each panel. A strong grip means solid metal. Weak grip or slipping means body filler underneath. Use it on any panel that looks slightly off.
The PPSR Report
Not every tool is physical. This one is essential. Run a PPSR check before you pay anything. It costs only a few dollars. It tells you three critical things:
| The check reveals | Why it matters |
| Money owing on the car | The car can be repossessed after you buy it. |
| Written-off status | The car may be unsafe or hard to insure |
| Stolen status | You could lose the car and your money |
Then match the VIN on the report to the VIN on the car and compliance plate. A mismatch is a serious red flag.
Your Complete Inspection Kit
Here is the full kit in one place. Tick each one off as you build it.
| Tool | Priority | Main job |
| OBD2 scanner | Essential | Read hidden faults |
| Tyre tread gauge | Essential | Check tyre wear |
| Paint thickness gauge | Essential | Spot crash repairs |
| Block tester | High | Detect head gasket failure |
| Torch and mirror | High | Inspect hidden areas |
| Magnet | Useful | Confirm body filler |
| PPSR report | Essential | Check finance and history |
How to Inspect Step by Step
Keep it simple. Work in this order.
- Run the PPSR check before you visit.
- Scan the car with your OBD2 tool.
- Test the tires with the tread gauge.
- Check the panels with the paint gauge and magnet.
- Run the block tester on the cooling system.
- Use the torch and mirror underneath.
- Match the VIN to the report.
This routine takes under an hour. It can save you thousands.
What These Faults Cost to Fix
The tools are cheap. The faults they catch are not.
| Hidden fault | Caught by | Typical repair cost (AUD) |
| Blown head gasket | Block tester | $1,500 to $4,000 |
| Worn tyre set | Tread gauge | $600 to $1,200 |
| Crash repair respray | Paint gauge | $1,000 to $3,000 |
| Transmission fault | OBD2 scanner | $2,000 to $6,000 |
| Hidden rust | Torch and mirror | $1,000 to $5,000 |
One catch pays for your whole kit many times over.
Conclusion
A used car can be a smart buy or an expensive mistake. The difference is preparation. The right tools for a used car inspection take the guesswork out of the deal. An OBD2 scanner, a tread gauge, and a paint gauge catch the big problems. A block tester, torch, mirror, and magnet cover the rest.
A PPSR check protects your money. None of it is hard. None of it is expensive. And all of it can save you thousands. So before your next viewing, build your kit of inspection tools. Inspect with confidence. Buy with peace of mind.
Frequently Asked Questions
What tools do I need to inspect a used car?
Start with three. An OBD2 scanner, a tire tread depth gauge, and a paint thickness gauge. Add a block tester, a torch, a mirror, and a magnet for a full check. Run a PPSR report before you pay.
Can I inspect a used car without a mechanic?
Yes. The right tools do most of the work. You just need to know what to look for. For a high-value car, book a professional inspection as well.
How do I check if a used car has been in an accident?
Use a paint thickness gauge on every panel. Factory paint reads consistently. One panel that is much thicker has likely been resprayed or filled. A magnet helps confirm hidden body filler.
How much does a used car inspection toolkit cost?
The three essentials cost roughly $75 to $290 in total. The full kit still costs far less than a single major repair, like a $1,500 head gasket job.
What is a PPSR check, and do I need one?
A PPSR check shows if a car has money owing, is written off, or is stolen. It costs only a few dollars. Always run one before you hand over any money.

