With the SD's the Speedo correction has to be done thru the ABS module. This precedure is done with a scan tool like the NGS or equivalent. To have Jody do this with the tunes on the chip will require custom tunes set up based off the tires revs per mile. When you want to change back to smaller tires or go bigger if have to get new tunes or your shift points will be off. Anything over 35" get the superlift truespeed and that wil take care of you. Other then that just go to someone with the scan tool I mentioned and have them recalculate your speedometer.
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