Three standard tires come on the various 2007 Ford Expedition models: 265/70R17 all-season, 265/70R17 all-terrain, and 255/70R18 all-season. Optional wheel and tire packages include 265/70R17 all-terrains, 18-inch alloys with 255/70 all-seasons, and 20-inch chrome alloys with 275/55 all-seasons. Whatever set of rims and rubber finds its way to your Expedition, it’ll be directed by a variable-assist rack-and-pinion steering assembly.