Odometer fraud increasing in used-car market, experts warn The number of vehicles on the road with a rolled-back odometer increased by 13% this year, CARFAX says. KABC Vehicle experts are warning anyone in the market for a used car to be on the lookout for rolled-back odometers, which can trick consumers into believing a car has less mileage or wear and tear than it actually does. According to CARFAX, the number of vehicles on the road with a rolled-back odometer increased in 2020 by 13% compared to the previous year. "If you are shopping for a used car, this should be on your list of things that you are looking at," said Emilie Voss, public relations director of CARFAX, a vehicle history website for buyers and sellers.