I know this has been discussed before. Maybe do a search for "speedo". You need to change your speedometer gear. It's not too hard, and it's just a different # of teeth. You could play with the numbers on http://dirtroad.com/gear.htm to find out the percent change of your new tires. Mine hits about 10%, thus 50 = 55 mph.
I'm on here so much, I have carpal tunnel reader syndrone.
/wwwthreads_images/icons/smile.gif Now on the late model stuff where the speed is measured by a sensor there may be a re-programmable element somewhere, but on the old stuff, there is a little transmission that goes in between the tranny speedo output nipple and the cable. It is like a little in-line gearbox and you can get them at the speedo shops. I have one on my pickup because at one time it had different sized tires. Usually the gears available at dealerships are only correct for the tire sizes and gear ratios that the Jeeps came with from the factoreeeee./wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif*** Here is something I bet you didn't know.......SOME TRUCKS have a little "transmission" in the back of the speedo; or hanging on the tail end of the last transmission; a little gearbox which is shifted by vacuum, air, or electricity because some trucks have a TWO-SPEED AXLE and when you shift the axle, the speedo has to compensate for the difference in driveline-turns-per-mile./wwwthreads_images/icons/crazy.gif So you could find a wrecked out truck and nab the changeover transmission off the back of the speedo. Who knows, it just may be the ratio that you need./wwwthreads_images/icons/tongue.gif
A Jeep Skunkworks run by Moonguys/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/tongue.gif/wwwthreads_images/icons/laugh.gif, buildin' the ultimate SNOJEEP!
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