I've got a 2005 Sierra 1500 2WD and I just had some new tires put on it. I orderd some Yokohama Gealander HT/S 245/70/17's for it. When I got to the shop they ordered the wrong ones (265/70/17). I decided to go with them still because the still would fit and it just would throw off my speed a little. Anyone know of a cheap easy way to adjust the speedometer cable speed to work correctly? I've been driving a few days with these tires and I kinda like em.

 

I think the computer has to be re-programmed but not 100% sure.