2011 F-250 w/ 39x14.5 tires question

[7.62x51]

On a new F250 w/ big tires and stock 3.55 gears....what steps need to be taken so the speedometer AND mpg readout is accurate again?

Getting over 28 mpg with 39s! lol

Thanks in advance

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[Matts00GT]

Tune. It's a digital speedometer so you can adjust it with most handheld tuners.

 

[7.62x51]

Thanks Matt, appreciate it. Anybody recommendations on which tuner to use? Or should I just go get it tuned at a shop somewhere? Im in coronado, san diego btw if there is a local tune shop around

 

[NJStang86]

For something simple like that, a mail order (actually email) tune will do.

 

[Matts00GT]

Thanks Matt, appreciate it. Anybody recommendations on which tuner to use? Or should I just go get it tuned at a shop somewhere? Im in coronado, san diego btw if there is a local tune shop around

Shop is always my preference but mail order would be second depending on your mods.