The Steinwinter Supercargo 20.40 Concept was an all-new way to solve the issues that heavy, un-aerodynamic and difficult to maneuver tractor trailers suffer from. Designed by Manfred Steinwinter in 1983, the Steinwinter Supercargo 20.40 Concept debuted at the 1983 Frankfurt Motor Show. Measuring a scant 1,170 mm (about 46-inches) tall, the Steinwinter Truck Concept was lower than many sedans of the day.
Powered by a 400-horsepower OM442 Mercedes-Benz engine, the Steinwinter Supercargo 20.40 Concept had (at the time) novel innovations including ABS, adjustable air suspension, full climate control and a limited-slip differential. It could haul 150 cubic meters of cargo while taking up much less space. Several permutations of the Steinwinter Supercargo 20.40 Concept were tested with mixed results. 
This was a modular design, one that was conceived to be used as a solution for many forms of cargo mobility. It could be converted from a cargo hauling vehicle to a tractor and even a public transport (bus). Unladen, it was extremely maneuverable and easy to park. The powertrain was modular as well, allowing a variety of different power units.
The cockpit looked like a sports car with bucket seats, a car-like steering system and an immensely low seating position (as low as a Corvette). There was enough space between the driver and passenger seat for a small bunk, or equipment storage.
Early on, truck manufacturers like DAF and Isuzu showed interest in the design, but nothing came of it. Even Mercedes-Benz, who was instrumental in the Steinwinter Supercargo 20.40 Concept’s design showed little interest in production.
Unfortunately, despite its modern approach and innovative design solutions for hauling goods, the Steinwinter Supercargo 20.40 Concept suffered from enough issues to make it undesirable for the auto industry. Heavy understeer, poor visibility and the fact that it overheated often (as engine cooling was difficult) along with many drivers disliking the incredibly low seating position helped kill the Steinwinter Supercargo 20.40 Concept.
As the curtain fell on this unusual concept, one final acknowledgement of its futuristic design came from Hollywood by way of the short-lived television show Highwayman. They used the design for one of their trucks. Yay…
Speaking of future trucks…
