My Unimogs use off road heavy duty truck tires. Unimogs are technically road going tractors and at best they are geared for about 60 MPH. This is good thing as the few tires built for the 335/80 R20 required size and load rating are only rated for 60 MPH. Some folks on occasion go faster but there are lot of internal parts of the tire moving around with 16,000 pounds of weight on them so they heat up. Luckily the military does use that size and are somewhat obsessive about changing nearly new tires so many of us buy used military tires. The new tires are about $600 each with used ones in the $300 range not including shipping. They have a heavy off road cleated tread that basically grinds itself off when on the road so the mileage isn't that great. The tread is directional but Mercedes says to mount the front tires in reverse of the tread direction when used on road to extend the tire life. They are definitely a handful to work with.