if the car has been to a reputable shop it's mileage is recorded which is where the car fax comes in. Problem is a lot of smaller shops do not do so : I was also under the impression that the mileage was recorded and stored ourside of the instrument cluster ?
Back when I was working for Ma Mopar 2007-2008 we were told the mileage was stored in the ECM, cluster and one other module. If you replaced one module, the other two had to agree and the new module would receive the correct number of miles. There was exceptions (Neon for example) but that was an older car by then. There were situations when that factory touch screen scan tool had to be used to input some information.
Unless Mopar has changed things, the odds of changing an odo are damn slim. And I doubt they changed things.
