The show offered mixer, dump, and other heavy-duty truck model operators an early look at diesel engines that meet reduced nitrogen oxide levels the Environmental Protection Agency requires for heavy-duty, on-highway diesel engines beginning next January
The show offered mixer, dump, and other heavy-duty truck model operators an early look at diesel engines that meet reduced nitrogen oxide levels the Environmental Protection Agency requires for heavy-duty, on-highway diesel engines beginning next January. The centerpiece of Mack TrucksÌ exhibit was a Granite Axle Forward GU7 dump, with (2007 EPA-compliant) MP7 engine and diesel particulate filter, plus diesel exhaust fluid (DEF) tank and Selective Catalytic Reduction (SCR) catalyst. In choosing the SCR method to meet the EPA’s lower NOx threshold, the manufacturer positioned the DEF tank on the driver’s side adjacent to the fuel tank, while the SCR catalyst is mounted on the opposite side, next to the diesel particulate filter.
The catalyst will draw the DEF (urea) at designated intervals to provide after treatment of exhaust from the diesel particulate filter, bringing the engine into EPA 2010 compliance. In addition to Mack Trucks, Cummins Inc. is using SCR for its next generation of on-highway power. At World of Concrete, it displayed a catalyst that will equip the two engines, ISL9 and ISX11.9, best suited to mixer and dump trucks. The latter engine will replace the ISM. The manufacturer will unveil its 2010-compliant on-highway engine family at next month’s Mid America Trucking Show in Louisville.