What It Takes to Run 40s on Your Rig | Harry Situations

Nothing commands respect on the trail like 40-inch tall Nitto Trail Grapplers, but it takes a lot more to go from a 37-inch tire to a 40-inch tire than it does to go from a stock sized tire to a 37-inch tall tire. We aren’t just talking about a lift, kit, the weight and leverage from such a large diameter tire requires upgrades to axles, gearing, and braking in order to safely run such a large tire. Harry Wagner from Harry Situations has upgraded all of these components on his ’77 F150 in order to run 40-inch Nitto Trail Grapplers. Harry compares the ground clearance, weight, acceleration, and supporting modifications necessary to run 40-inch Nitto Trail Grapplers compared to 37-inch Nitto Ridge Grapplers on his ’77 Ford F150. Then he hit the trail and went wheeling with Mike Henderson from All-Terrain Family. Upgrades made for the bigger tires include: • Super Duty axles built by Axleline with disc brakes, Detroit Lockers, and gears (the lowest you can get for a Sterling axle)