1992-96 F-Series/Bronco Speedo Calibration Procedure

Created by Tyler Rodriquez / 3 min read
Date Created: 2/24/2024
Last Updated: 2/22/2024

Calibrate the speedometer on your 1992-1996 F-Series Truck or Ford Bronco with this simple procdure.

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If you are needing to correct the speedometer calibration on your 1992-1996 Ford F-Series Truck or Bronco, follow these easy steps.

Wire With Alligator Clips On Ends

Checking the Conversion Constant:
  1. Press and hold the RESET button on the speedometer while turning the key to the RUN position.
  2. Release the RESET button. The pointer will move, and codes will appear on the odometer display. An "E" indicates English display mode (MPH), while a lowercase "o" indicates metric mode (KPH). Ensure the display mode matches the graphics.
  3. Press and release the RESET button again. The odometer display will show the conversion constant and "CAL."
  4. Verify the conversion constant displayed matches the correct value for your vehicle.
  5. Turn the key to the off position to exit the test.

Reprogramming the Conversion Constant:
  1. Locate the dealer mode programming connector below the center of the glove box. The dealer mode enable wire on all vehicles is Circuit #567 (LB/Y).
  2. Insert a metal clip into the service wire panel connector and connect the other end to the vehicle ground with the key OFF.
  3. Turn the key to the RUN position while holding down the trip odometer RESET button on the speedometer, then release the RESET button.
  4. The speedometer will move, and the display will show English/Metric modes and revision levels. The last number is the dealer mode programming lockout count.
  5. Press and release the RESET button to show the current conversion constant and "CAL."
  6. Press the odometer SELECT button to change the conversion constant to the correct value.
  7. Press and release the RESET button to lock in the new conversion constant.
  8. Turn the key off and remove the ground wire. Verify the speedometer operation.

Finding Conversion Constants for Tires:
  • For 15-inch wheels, multiply the tire's revolutions per mile (at 45 MPH) by 0.0135. For 16-inch wheels, multiply by 0.015.
  • Example: BFG AT 33x12.50R15LT/C with 636 revs/mile: 636 x 0.0135 = 8.59 (conversion constant).

Popular BFG All-Terrain Tires Conversion Constants:
  • 30x9.50R15LT/C: 705 rev/mile, conversion constant = 9.52
  • 31x10.50R15LT/C: 677 rev/mile, conversion constant = 9.14
  • 32x11.50R15LT/C: 656 rev/mile, conversion constant = 8.86
  • 33x12.50R15LT/C: 636 rev/mile, conversion constant = 8.59
  • 35x12.50R15LT/C: 599 rev/mile, conversion constant = 8.09

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About the Author

Tyler has written content for Late Model Restoration for nearly 8 years, producing over 300 articles. As an avid New Edge fan, Tyler has owned 4 2004 Mustangs and an 88 Convertible Fox Body. Read more...