Two Pickups with more similarities, such as the body structure, ground shadow size, height, and maximum occupancy, than differences, like the powertrain, horsepower, and starting price. First of all, the 2016 GMC Sierra 2500HD Regular Cab pulls more horsepower than the 2015 Ram 1500 Quad Cab Diesel. Also, the 2016 Sierra 2500HD Regular Cab is priced $3,665 lower compared to the base MSRP of the 2015 1500 Quad Cab Diesel. Among similarities are the body structure, ground shadow size, height, and maximum occupancy.