pjay9 wrote:
BTW, If you have a chip for your engine...many have a way to change the speedo for tire size...I fine tuned the speedo using the GPS speed and then a 5 mile check along the freeway to see if it was a good setting...did the 5 miles in 5 mins +/- at 60...best you can do to keep steady! Good luck!
I used the Snap-On computer scanner from work to reprogram mine, on my 99 Ram the odometer calibration was in the ABS computer. I simply programed in the revolutions per mile from the tire manufacture. It only took about 5 minutes. My 19.5's are about three inches taller than the stock size.
