Speedo/odo recalibration thoughts
I increased tire size from 17" stock to 19.5" tires. The speedometer is off by 2-3 mph; therefore, I presume the odometer and computer generated mpg readings are off also. Local mech wants $95 to rec...
Forum Discussion
I am pretty sure that tuners (like a SMARTY or SMARTY JR) can recalibrate the speedo. I seem to remember that was an option on my Smarty JR. Not saying you should buy one just for that, but maybe if you get on one of the Cummins forums you could find someone local who could recalibrate for you.
