Two Pickups with more similarities, such as the body structure, starting price, height, and maximum occupancy, than differences, like the horsepower and ground shadow size. First of all, the 2017 Toyota Tundra CrewMax Cab produces fewer horsepower than the 2017 GMC Sierra 2500HD Double Cab. And finally, the 2017 Sierra 2500HD Double Cab is slightly larger than the 2017 Tundra CrewMax Cab. Among similarities are the body structure, starting price, height, and maximum occupancy.