Hundreds of thousands of cars, vans and motorcycles currently in use have had their odometers tampered with to boost their value, according to car history checking company HPI.
Quoting BBC figures, it said more than 600,000 cars and 100,000 vans and motorcycles have been "clocked". According to the Office of Fair Trading the practice is estimated to cost car buyers nearly £580 million a year.
Studies for HPI have found nearly 8% of all vehicles have odometer readings inconsistent with recorded history of their mileage, which is an important factor in decidingcar insurance premiums.
HPI says modern odometers make it hard to detect the fraud and is urging buyers to carry out proper history checks before making a purchase.
"Unscrupulous sellers see the clocking of a vehicle as an easy way to raise its price and make some extra cash by putting thousands of pounds onto the price tag," said Nicola Johnson, Consumer Services Manager for HPI.
"These latest figures just confirm that clocking is one of the greatest threats facing used car buyers today. Unfortunately modern digital odometers make it even easier for clocked vehicles to evade detection, as the traditional tell-tale signs of damage to screws or poorly aligned number is not visible."
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