Results 1 to 2 of 2

Thread: '04 F250 Speedometer Correction

  1. #1
    Advanced Tuner
    Join Date
    Apr 2014

    '04 F250 Speedometer Correction

    Anyone had any luck getting the speedometer (along with the broadcast VSS PID in the scanner) corrected for tire size? I've tried correcting every parameter for the given tire size that is found in the ECM and TCM.

    Truck has 3.83 gears, and 38" tires.

    Speedometer parameters set as follows:
    Use VID = Disabled
    Final Drive Ratio = 3.83
    VSS Tire revs per mile = 530.74
    N/V Base = 32.7965
    N/V Min Learned = 32.0000
    N/V Multiplier = 10

    Even changing the N/V drastically seems to make no difference to the error between actual vs indicated.

    Any help would be greatly appreciated!

  2. #2
    Join Date
    Jul 2019
    Only thing I changed was VSS to 34.5 because I have heard ecm doesn?t do well over 35 in SCtX4 would only allow me to go up to I think 34 ? try doing it 1/2 VSS Instead of 383 use
    Last edited by Jeffrey Kavney; 10-08-2019 at 05:29 AM.