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1999-10 Mustang Ford Performance Speedometer Adjuster

1999-10 Mustang Ford Performance Speedometer Adjuster


Market Price $219.99 You save $20 (9%)

Part # FOR-M-4209ADPT-AC

Ford Performance M-4209ADPT-AC

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1 In Stock

Availability: In stock



  • Used to correct speedometer because of tire size or gear ratio changes
  • Easy 4 wire installation
  • No reprogramming of PCM necessary
  • Fits 1994-2004 Mustang with manual and automatic transmission
  • Fits 2005-2010 Mustang with automatic transmission. Will correct speedometer to equivalent of 10% gear ratio change higher or lower
  • Fits 2005-2010 Mustang with manual transmission. Will correct speedometer. No limit on magnitude of gear ratio change for manual transmission vehicles
  • The Speed-Dial scales a frequency based vehicle speed signal up/down to maintain accurate vehicle speed indication to the instrument cluster and PCM.

    NOTE: To maintain cruise control function on 2005-2010 Mustang automatic and manual transmissions gear change is limited to equivalent of 5% higher or lower ratio (<+/-5% change). For example a gear change from 3.55 to 3.73 results in a gear ratio reduction of 4.8% so cruise control will continue to operate normally. A gear ratio change from 3.55 to 4.11 results in a gear ratio reduction of 13.6% so cruise control operation is lost.