fyi.... we haven't been able to "recalibrate" speedo's on vehicles for about three years at the dealer. They've also taken away adjusting the tire psi threshold so if you change to a larger show pony tire that can be run at a lesser psi than a factory tire (think 2500+ with lift etc...) you get to live with the low tire psi warning.
That seems ridiculous. The factory took away that adjustability in the software? Why would they do that? Have the dealers all cried foul back to the factory? More reasons why my 06 5.9 cummins will be the last truck I ever buy, as long as I can keep it from rusting away or getting wrecked
