I just got done creating a one ton burban, yay! got a problem though... I put in 4.88's and am running 35" tires on the street and 38's for the trail. not too worried about the speedo being right with the 38's, but it shows me going about 75 or so when I am actually doing 65 with the 35's. I found info on recalibrating my DRAC, if it had one, but I either cant find it or it doesnt exist as a seperate entity. also it is electric, and cant find gears for it if they even exist, so I cant figure out how to recalibrate it the cheap and easy route. (GM wants $500 to fiddle, and say they prob. cant get it right anyway) any ideas? 1991 GMC Suburban 3/4 ton with a 4L80E, Full Float 14 rear, Dana 60 front, 4.88's and Lockers... thanks in advance!