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 Chevrolet Silverado 2500HD Regular Cab has a more powerful engine than the 2015 Ram 1500 Quad Cab Diesel. Also, there is a notable difference in the starting price of the 2016 Silverado 2500HD Regular Cab, which is $4,245 less than the base MSRP of the 2015 1500 Quad Cab Diesel. Among similarities are the body structure, ground shadow size, height, and maximum occupancy.