Ford Speedometer Gear Calculator, Speedometer Gears Formula for Calculating Speedometer Gears The following formula will work for any GM, Ford or Chrysler vehicle and is very useful when there is no established baseline from which to work from such as replacing a transmission in a vehicle that was purchased without a drive line. This is very useful when there is no established baseline from which to work from such as replacing a transmission in a vehicle that was purchased without a drive line! This will calculate the speedometer driven gear needed to properly calibrate your speedometer. Find the correct speedometer driven gear size with our speedometer gear recalibration calculator, plus learn the formulas to calculate it. Use this TCI Auto Speedometer Gear Calculator Formula for any GM, Ford or Chrysler vehicle. This is because your speedometer is controlled by two small gears that are optimized for a particular combination of tire size, rear-end gear ratio, and transmission type. Always recheck the speedometer calibration! You can either enter your radial tire dimensions or actual measured values below. Select which one you want used for calculations with these radio buttons: Use Measured Diameter (best) Use Radial Designation May 8, 2020 · Get the right speedometer gear for your 1979-98 Mustang based off of rear gear ratio & tire size! No guessing with this Mustang Speedometer Gear Calculator! 1967 - 1973 Mercury Cougar (and Ford Mustang) Speedometer Gear Calculator Speedometer Gear Calculator Changing tires to a new size or changing rear-end gears can have an impact on speedometer accuracy. . otiasi, f1u, pdj, slvvye, 2mo, vyvv, vctl, w2e6, s5rdqpu, yjokfr,