Hypertech Speedometer Calibrator 2005-2012 Dodge Ram

Changing tire and gear sizes can have an adverse effect on your speedometer and odometer readings. To correct this, Hypertech has assembled some of the best features from their series of programmers and tuners into one stand-alone unit.
Hypertech speedometer calibrators will adjust for a wide range of tire sizes and gear changes (not all applications can adjust for gear changes) to keep your speedometer reading properly without the additional cost of buying a complete tuner.
Installation is as easy as plugging one of the calibrators into your vehicle's OBDII diagnostic port, and while you're there, they can even read and clear diagnostic trouble codes.

Speedometer Calibrator