How to re calibrate speedo on a 2004

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2/28/16, 02:42 PM

scf100

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How to re calibrate speedo on a 2004

Have a 2004 Mach 1 and switched to 18 inch wheels....still running 3.55 gears but now speedo 5 mph too fast.....checked with a gps app

so how to re calibrate?

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2/28/16, 02:47 PM

Getportfolio

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My friend used a diablosport hand held tuner. That's was years ago though. However, it worked.

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2/28/16, 03:28 PM

SplitSecond

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Yup, the PCM needs to be flashed and recalibrate to new tire height. A hand held tuner would do the trick, a tuner shop would be able to do it, a dealer should be able to do it for you too.