think our mileage was rolled back

[ProudUSNavyWife]

We bought our 2000 Ford Mustang GT with 38,949 miles on it on 3/30/2004.

We just came home from a trip to FL, by using mapquests directions it said it would be 1,077 miles (from our home to where we went in FL) When we got to FL our odometer said we had only gone 866 miles. On our way home today, we set up our odometer with the mile markers and it came out to be off by at least 7 miles (in a 30 mile span)

We also had to have the ring & pinion replaced at about 50,000 miles.

We did a car fax report on the car, and found out that it has had 3 other owners besides us.

The owner (a dealership) before us bought it at an auto auction. The car then sat on a dealer lot from 10/16/2002 with 14,088 miles until we bought it on 3/30/2004 with 38,949. It is very odd that the put on 24,861 miles in 17 months, and the mileage when we bought it (3/30/2004 with 38,949) going by the industry average it should have had about 60,000.

We now think that the mileage has been rolled back. Does anyone know is there is a way to tell if the mileage has been rolled back? And how I would go about finding out, and what to do if it has been.

The reason we think it has been is, having to over haul the rear at about 60,000 miles. When we bought the car (the tires) where not the factory tires (they had obviously been replaced once before) and we just bought new tires for the car. Also new brakes and rotors (the man who replaced our brakes and rotors said that they had been cut twice already) And also the mileage being off.

Any advice would be greatly appreciated. Thank you for reading

[1989GT]

Not sure how to tell if the odometer has been rolled or not, but I will say this. I've never seen a ring and pinion need to be replaced from just driving. I have seen them give way in a racing environment. I curious to as why a dealership would but 27k miles on a car. I'd say your best bet would be to take it to a ford dealership and tell them what you suspect and have them look it over. Possible the car's just been driven really hard. Also what gear ratio was in the car? And what ratio did you have put in.
-Ryan

[WHITE04GTVERT]

Sounds like your stang has been modified. The only way to roll back mileage is with the ford dealership diagnostic computer, as the mileage is stored in the computer and even if you change it, it has to be done with there computer or the car will not crank and run until it has been programed with there computer. If your mileage is off by 7 miles for every 30 miles then you have the wrong size tires and the computer has not been recalibrated to the new tire size. you can do this your self by buying a (predator or hypertech type programmer) and connecting it to the diagnostic terminal. If you don't won,t to do this I would take it to a ford dealership and ask them to do it for you. I hope this helps.