For our test, we used sets of 35x12.50-15 BFGoodrich All-Terrains and Mud-Terrains wrapped around identical sets of 15x8.5 Center Line Style 31 wheels. The mounting and balancing were performed by 4 Wheel Parts Wholesalers. Our test mule was a '79 Ford Bronco equipped with a 4-inch lift, open diffs front and rear, and stock gearing. Each set of tires was run over the same terrain, which included sand, mud, and both wet and dry trail obstacles, as well as wet and dry pavement. One person did all the driving for consistency.