115% efficiency improvement

At the opening of the Mid America Trucking Show in Louisville, Kentucky, Freightliner is claiming its SuperTruck project has achieved a 115 per cent freight-efficiency improvement. The announcement was made as the SuperTruck was unveiled as the centrepiece of the Daimler stand at the show.

The SuperTruck ran a five day, trial run, recently, and over the 312 mile (500 km) round trip on Interstate 35 between San Antonio and Dallas. Running at 65,000 pounds (29.5 tonnes) and a speed of 65 mph (105 km/h), the truck achieved an average result of 12.2 miles per gallon (5.2 km/l).

The truck was built as part of a joint project with the US Dept of Energy to reduce fuel use by 50 per cent. Both parties put $40 million into the project. The truck includes a number of newly developed aerodynamic components and a fully integrated Detroit drive train, with a heavily modified DD 13 engine and Daimler’s 12 speed AMT.

Other items like mirror cameras and an articulating grille which opens during low-speed and high-torque conditions to maximise cooling flow and automatically closes at highway cruising speeds to reduce aerodynamic drag.

The project is one of four funded by the US Government to stimulate fuel efficiency research. As a result, the competing teams are unwilling to go into great detail about technologies used in the SuperTrucks.

Apart from aerodynamic savings and a drive line designed for low rev/high speed running, a number of innovative strategies have been followed. These are said to include engine waste heat recovery, some hybridisation in the driveline, low rolling resistance tyres, clutch disengagement freewheeling when motive power is not needed and lower friction components all round.