First seen at the IAA Hanover Truck Show in 2006, the launch of the Unimog U 20 must be one of the longest in recent truck history, as the smallest addition to the Unimog range is about to reach the market.
The U 20 is the first Unimog to adopt a cab-over design, using the cab from the Brazilian Mercedes-Benz Accelo light truck, designed originally by the Mayflower Corp. before the U.K.-based vehicle designer entered receivership. Unimog vehicles of a similar size have used a semi-forward control cab. The U 20 cab is an all-steel construction, unlike the glass-fiber-reinforced-plastic cab used on the Unimog U 300. A standard stowage box is fitted behind the cab.
According to Mercedes-Benz, the U 20 has been designed for small- to medium-sized local authorities as well as gardening and landscaping contractors. Although it is the smallest Unimog, Mercedes claims that it is just as capable as the larger models, sharing familiar features such as permanent all-wheel drive, single tires front and rear, differential locks, portal axles to maximize ground clearance, coil springs, power take-offs (PTOs), and onboard dual-circuit common hydraulics. Standard equipment also includes an air-conditioned cab.
Power is supplied by the four-cylinder Mercedes-Benz OM904 LA turbocharged diesel engine that powers models in Mercedes Atego and Vario European truck ranges. This version is rated at 147 hp (110 kW) at 2200 rpm, with maximum torque of 428 lb·ft (580 N·m). The Euro IV-compliant engine uses Mercedes Bluetec selective catalytic reduction technology to control emissions, using a urea additive.
An eight-speed manual transmission offers maximum speeds of 0.7 to 56 mph (1.1 to 90 km/h) at the rated engine speed of 2200 rpm. Auxiliary drive systems include numbered and color-coded hydraulic connections at the front of the vehicle and a PTO at the front mounting plate.
Besides the front mounting plate, there is also a rear attachment area designed for smaller quick-change equipment.
The chassis is a shortened version of the smallest U 300 chassis, providing a wheelbase of 2700 mm (106.3 in)—380 mm (15.0 in) shorter than the larger model. The U 20 can be supplied with a dropside/dump body, and other bodywork and equipment can be accommodated on the chassis, too.
Overall length will vary according to bodywork, while the vehicle measures 2150 mm (84.6 in) wide, 2700 mm (106.3 in) tall, and offers a 12.8-m (42-ft) turning radius. Mercedes quotes a gross vehicle weight between 7.5 and 8.5 t (8.3 and 9.4 ton), with permitted axle loadings of 4.8 t (5.3 ton) for both axles to offer a broad tolerance when equipment is fitted. The U 20 can handle a gross combination weight of up to 18 t (19.8 ton), providing a trailer capacity of up to 11.2 t (12.3 ton).
Unimogs are built at the Mercedes-Benz Special-Purpose Vehicle division, based in the Mercedes truck plant at Wörth near Stüttgart, the center for Mercedes heavy-truck production in Europe and the largest truck production plant in Europe. The Special-Purpose Vehicle plant produces some 2000 Unimog models annually.
Mercedes-Benz recently demonstrated a range of equipment with the U 20 in Germany, including a snow plow and gritter, snow blower, snow blower/cutter, front PTO-driven boom mower, a wood shredder driven from the front PTO shaft, and a vehicle equipped with a cable winch and crane.