New gears = Messed up Speedometer

[obi-1]

@BlueZ06

those things can only put a tune on 1 vehicle at a time… changing the speedo calibration is considered a written tune

I picked up a hypertech programmer for about 150 on eBay for my truck.
(Maybe 170?) You can only use it on 1 vehicle at a time.

You just type in what gears you have and tire size and it calibrates the speedometer for you.