MYRTLE BEACH, SC (WMBF) - Your odometer says a lot about your car. It can determine it's worth, it's resale value and even the amount you pay for car insurance. However, in a WMBF News Investigation, we learned odometers don't have to be that precise.
"As long as the odometer in that play area, that gray area, they say it's fine," said mechanic Jonathan Suggs, noting there is no government body that regulates the accuracy of odometers. "The margin of error is probably around 2 or 3 percent. Nobody really knows. That's one of those magical numbers that the consumer never really understands or hears. There's no specifics about it."
In our investigation we found there are only laws against tampering with it, but nothing about accuracy. There is only a voluntary standard from the Society of Auto Engineers of plus or minus 4 percent. So if you're driving from Myrtle Beach to Atlanta, your odometer could be off by more than 14 miles. That's just a single one-way trip.
In order to test how accurate odometers are, we went to the Myrtle Beach Speedway. We tested five different cars, trucks and vans. The Myrtle Beach Speedway is a half mile track. However, we measured it with our mile marker to be precise.
The first car we tested was a 2008 Subaru Impreza. The odometer on the Subaru was off. It went a full 25 feet past the mile marker. A 1998 Nissan Maxima and a 1999 Mazda Miata also overshot the mile.
The Nissan came in more than 50 feet past our measured mile, while the Miata was slightly more accurate, passing one mile by exactly 48 feet. According to our tests, the most accurate vehicle was our news van, a 2008 Ford Econoline.
However, it still passed one mile by 15 feet. As for our final test, a 2000 Chevrolet Silverado pickup went 224 feet past one mile. That's an error of more than 6 percent.
Each and every odometer we tested recorded a mile too slow. That could be very costly for any future owner of these cars, according to car experts.
"Mileage is very important for the value of the vehicle," Jack Nerad, who works for the car buying guide Kelley Blue Book. "When you look at our values at www.kbb.com, it makes a big difference."
Nerad says if you're looking to buy a used car or truck, make sure you look at the tires. If they're over or under-sized, the vehicle you're buying could have an inaccurate odometer.
"There is just the potential for mistakes," he explained. "Some people can innocently put on oversized tires, and you wont get a true odometer reading. That's doesn't mean they're trying to commit fraud. That's just the way things are."
Mistake or not, an inaccurate odometer can cost you big bucks in the long run. In an average year, most drivers put on 15,000 miles on their car. In the case of the Chevy Silverado, being off by 4.2 percent means an extra 630 miles not being recorded. Over 10 years, that means 6300 extra miles on your odometer.
Even our most accurate vehicle, the live van, was off by 15 feet. Over the course of 10 years, you're looking at an extra 2800 miles.
"If it's incorrect we have to disclose it, and of course the value of the car comes down because of that," said Russ Boykin, general manager at Hyatt Pontiac which sells used and new cars. "You obviously want to do a car history, whether it's through a Carfax or an Autocheck, to see what the history of the car is."
However, even with a vehicle history report, car experts say the No. 1 piece of advice is to keep your eyes open when it comes to a vehicle's mileage.
"If the interior looks worn and yet the odometer is showing very few miles, that may be a hint that something has happened with the odometer," Nerad commented.
Experts also recommend if you do change your tire size, make sure to also have your dealership change your odometer settings so it registers the proper mileage. They also say if you're not sure whether your odometer is giving you a correct reading, the best way to check its accuracy is to bring it to your dealership and have it electronically tested.