I just installed 4.10 gears and I was wondering what I had to do to get the speedo back to normal. I went to ford to have the computer flashed and they said they could not do it.
Thanks,...

 

speedcal is the only way as far as i know

 

You could get a handheld programmer too.

 

you need to get a new VSS.

 

Speedcal from dallas mustang or a handheld tuner or a custom tune(re-flash) Whats a VSS?

 

VSS = vehicle speed sensor it's an electronic device installed in the transmission that sends a signal to the ECU to let it know the speed of the vehicle which the ECU uses to control the IAC when you lift off the gas pedal and the car is coasting.

 

yea, i just dont know abbreviations that well. They dont sell aftermarket VSS for the 99-04 stangs do they?

 

I doubt it, seems like this would be a dealer only item to me but I've never really looked for one either so I don't really know for sure about where to buy one.