diamler Chrysler's decision to market the Unimog , a converted German military vehicle, as a sports utility vehicle (suv) in the us has been questioned by the Sierra Club, a us -based environmental organisation, and the Worldwatch Institute, a non profit public policy research organisation based in Washington dc . "The Unimog is not a normal suv but is basically a heavy duty hauling truck. Diamler needs to be pressurised to make cleaner cars and to stop selling trucks as family cars in the us ,' says Alex Veitch of the Sierra Club Global Warming and Energy Programme. The chief executive officer of Diamler Chrysler has admitted that the vehicle did very poorly in Europe. "With dire warnings about global warming, we should be looking for ways to reduce emissions,' said Dan Becker, director of the club.