The Hummer H1 receives a number of important drivetrain improvements this year. Now labeled H1 "Alpha," the truck features a new 6.6-liter turbodiesel V8 good for 300 horsepower and 520 pound-feet of torque. This output is considerably better than last year's 205 hp and 440 lb-ft of torque, and GM says the new engine delivers better fuel economy, too. A new five-speed automatic transmission is also part of the package. It replaces last year's four-speed transmission and delivers a better low-speed crawl ratio and a higher maximum tow capacity. Other supporting changes to the driveline include stronger half shafts, bigger brakes and a new design for the H1's geared hubs that's said to improve smoothness during deceleration and stopping.

The H1 (the original Hummer's official name since the debut of the H2) is a civilian version of the High Mobility Multipurpose Wheeled Vehicle (HMMWV), or Humvee, used by the U.S. military. A.M. General, the current manufacturer of the H1, was awarded its first government contract to build the Humvee in 1983.