USA – Results from a federally-funded ‘SuperTruck II’ programme led by Navistar International Corporation – a subsidiary of the Traton Group based in Lisle, Illinois – have been announced, demonstrating 16 miles per gallon fuel efficiency and a 170% improvement in freight efficiency over the 2009 ‘SuperTruck I’ vehicle. 

The Class 8 demonstration truck-trailer combination was built as a hybrid vehicle between Navistar and German components group Bosch. It is powered by a combustion engine with high-voltage accessories and technologies. With contributions from Jacobs Vehicle Systems, the partners made improvements to combustion, friction, gas exchange, and airflow in the engine. A redesigned cylinder head with dual overhead cam engine and enhanced fuel system reportedly brought a 2% fuel economy improvement when compared to Navistar’s SuperTruck I from 2009. Aftertreatment system improvements included diesel exhaust fluid dosing, improved mixing and lower restrictions, new selective catalytic reduction (SCR) formulations for high-NOx reduction, and reduced cold-start activation time. Ultimately, the project achieved brake thermal efficiency of 55.2%.