Two Pickups with more similarities, such as the body structure, starting price, height, and maximum occupancy, than differences, like the horsepower, fuel economy, and ground shadow size. First of all, the 2017 Nissan Titan XD Regular Cab has a more powerful engine than the 2017 Toyota Tundra Double Cab, but it gets 2.5 more miles on a gallon of fuel. And finally, the 2017 Titan XD Regular Cab is slightly smaller than the 2017 Tundra Double Cab. Among similarities are the body structure, starting price, height, and maximum occupancy.