SPEEDOMETER CALIBRATOR 94-

Used to correct speedometer because of tire size or gear ratio changes Fits 1994-2004 Mustang stick and automatic Fits 2005-2010 Mustang stick shift Fits 2005-2010 Mustang automatic. Limited to equivalent of one step higher or lower gear change ratio (< /- 10% change) Tool scales a frequency based vehicle speed signal up/down to maintain accurate vehicle speed indication to the instrument cluster and PCM. Easy 4 wire installation No reprogramming of PCM necessary