F 250 2WD Pickup V6-4.2L VIN 2 (1998)
Speedometer Head: Adjustments
1. Remove the original driven gear.
Ts = Number of teeth on replacement driven gear.
To = Number of teeth on original driven gear
Va = Actual vehicle speed.
Vi = Indicated vehicle speed.
VSS = Vehicle Speed Sensor.
2. With Va, Vi, and To known, calculate new number of driven rear teeth.
NOTE: Use one of the following formulas.
^
Ts=(Vi x To)/Va
^
Ts=(To x new tire revolutions per mile)/(old tire revolutions per mile)
NOTE: Design accuracy is. -3/+8 km/h at 50 and 100 km/h (-2/+5 mph at 30 and 60 mph).
3. Round to whole number, dropping fractions less than 0.6, and rounding up if fraction is 0.6 or higher.