If you go with a bigger tire you need to program the computer. if you plus size than you need to do nothing to the computer. Ford limited the tire sizes you can put on the truck. As for tires it's just like oil. You just find what looks good to you because everybody has a opinion. I got great millage out of my original set of Continental. I just didn't like that they picked up small rocks So I have Good Year the ones with Kevlar. Now they pick up a slightly bigger rock. If I was ready tyo get new tires I would go back to Continental's