Hummer concept shrinks footprint 

David Phillips / The Detroit News

Hummer — once synonymous with big and brash and thirsty — is slimming down and going slightly "green" for the times.

General Motors Corp. will unveil a Hummer off-road concept at the North American International Auto Show on Sunday that features removable roof panels, fender flares and doors, and a 3.6-liter, V-6 engine that can run on ethanol.

The HX concept is also the smallest Hummer yet. It would rival the Jeep Wrangler in offering a lower-priced but still rugged, off-road vehicle to younger buyers. In the future, Hummer is banking on broadening its appeal worldwide by marketing smaller, more fuel efficient off-road vehicles.

In the United States, Hummer demand fell 22 percent last year.

The HX was engineered with permanent four-wheel drive to traverse trail conditions and provide for a variety of cargo needs. GM tapped three new, young designers to create the HX with the specific goal of drawing younger buyers.

With a 103-inch wheelbase, it is longer than the 2-door Wrangler but shorter than the four-door Wrangler Unlimited. When roof panels and roof assembly are removed, the HX can be transformed into a convertible. The HX also was designed with several roof assembly configurations, allowing it to be used as a sport-utility truck or a wagon with more cargo space.