sledfreak
New member
Well I"m at a loss, I got new tires on the truck, so I punch in the rolling diameter 33.54 and the speedo's 3 mph faster than the gps, so I punch in 34.00, it's still the same, so I punch in 34.58 which is the actual tire diameter and still the same 3 mph faster than the gps says, I don't know why it's doing it the last set of tires I had no problem, anybody have any ideas.
