Hey guys, I can get some 31x10.5 -15 BFG Mud Terrains for CHEAP. I was just wondering if they will fit on a stock 2wd 1986 Gmc Sierra. I was told by several tire places in my area that they will fit easily. However with 22 years of weight on the springs it may sag a little bit. I just wanted to make sure they will fit with out rubbing. I'm not worried about sitting still so much as I am hitting bumps and hard turns. Will they at least fit on the back? If not I will buy them to just resale them. Thanks!