So I'm getting a 6" lift and 35 X 12.5 tires on Friday and I've calculated that my speedo is going to be about 8% off due to the change in tire size. What do I need to do to get the speedo recalibrated?

I have a 2008 F-150 FX4 (5.4L).

I have talked to one local dealer and they said that they can't re-program it.

 

I haven't looked at them for the F150, but the power programmers I've seen for other cars included a section where you could enter the size tires installed and it would correct the speedo.

 

You can change the speedo with the SCT.

 

Yeah you can get yourself an SCT tuner such as the Xcal II, III or the Livewire with a custom tune and that would do it for you. Can't believe the dealership said they can't do it for you though. My dealership said they could recalibrate my speedo and adjust my shift points after I got my truck lifted for $80. I ended up getting the Xcal II with custom tunes though.

 

So if not getting a programmer, best shot is going to a dealership? I ask as I do plan on lifting my truck 6 inches sometime but sorta pointless to get a programmer with the L6 engine, at least to me....

Sides, by then I'll have the Cobra for go fast fun. hehe

 

Yeah dealership should be able to do it for you.