A WARNING to all motorists, you could be speeding and not even know it, but police will still slam you with a fine.
As police officers head out on our roads to monitor drivers over the Christmas period, motorists are warned to check the size and thickness of their tyres, as they could be affecting what they read on the speedo.
Maryborough Road Policing Unit Senior Constable Terry Parker said cars were designed to have specific tyres on them, and when those were changed, it affected the way the car measured its own speed.
"On every car is a tyre placard, which shows the specifications for the tyres it should have," Snr Const Parker explained.
"If the tyre size deviates from that, it affects the speedo."
The RPU officer said apps like TyreGuru can show the difference between how fast a speedo said a person was travelling, compared to how fast they were actually travelling, based on the make of car and the tyre used.
He said usually he would see a difference within 10% in the cars with the wrong tyres.
While Snr Const Parker has used this app out in the field, and has seen drivers caught in that situation, the officer said motorists would still get fined for speeding, even if their speedo said otherwise.
"I think people would still be able to tell if they're speeding, they would see that everyone else was going slower than them," he said.
"They're still breaking the law and have to pay the fine."
If you are unsure which tyres to use on your car, there are many different websites and apps available.
For example, the Bridgestone tyre size finder can show you the right tyre for your car after entering the make, model and year of your vehicle.
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