Hummer HX, Hummer HX is a vehicle which is classified as a concept hummer.It has brought a unique twist to the whole concept of what a hummer is and should be. This model focuses more on looking cool, and being compact, than on the "Mine's bigger than yours" mentality of the other hummers in the series. Features: New HX is powered by a 3.6-liter V6 gasoline direct-injection engine mated to a six-speed automatic transmission. The engine makes 304 horsepower and 273 pound-feet of torque and can run on E85 ethanol. With coil-spring suspension all around, the HX rides on 35-inch custom Bridgestone Dueler off-road tires.