I wrote some PC code once for a manufacturer of automotive electronics that was capable of doing things such as altering the odometer value. The auto dealer may have similar capability. The security involved with altering the odometer value is fairly sophisticated and I don't think you would be able to legitimately get ahold of the necessary information. The auto manufacturer has no way to differentiate your supposedly upstanding shop from a dishonest one. You may need to subcontract the dealer of whatever make auto you are working on to do this for you, and that may still be difficult. My experience is specific to one make of car so others obviously may differ.

Cory Spackman