[Aerkuld]

You're calculation doesn't sound too far off. Your numbers would work out with an average speed of around 36 mph, but you probably know that. It doesn't take much to lower the average speed and it just depends what conditions the owner(s) drove it under. Regular commuting in stop and go traffic would make a big difference for example. I could see that being the case on a lower mileage car.

What sort of mileage are you talking about and how big is the discrepancy?

With all of that said does anyone know where the odometer reads it's mileage? I suspect the instrument cluster is dumb and the mileage is stored somewhere in the DME. In other words, plug in any instrument cluster and it will read the same mileage, but that's just my guess . . .

Anyone?