Ok...Im running 16-inch probe gt rims that are 16x7 & Im running a 2-inch wide spacer/adapter-(front only) just to clear the front caliper & it also helps the rims clear the upper a-arms. Toyota trucks have a 5x114.3 lug pattern & thats the most widely used pattern used. Most Toyota's, Ford cars, Lexus, some BMW's & most Mitsubishi's have this same pattern. I personally wouldnt go any wider then a 7 or 7.5 inch wheel cause it will cause clearance issues. Here is a site that can help with some questions you may still have & hit me up if you have anymore. Donny http://www.tirerack.com/wheels/tech/techpage.jsp?techid=101¤tpage=95
