Issue link: https://read.dmtmag.com/i/26699
Steve Duley of Schneider reports only one incident of DEF going into the diesel tank, and the problem was fixed with minimal downtime. It happened because the restrictor in the filler neck had fallen out. 2010engine he 2010 drop in NOx to 0.2 grams has been accomplished by most truck makers with selective catalytic reduction. Even with SCR’s requirement for adding diesel exhaust fluid, SCR has brought basic improvements. That’s because letting SCR handle much of the NOx means less exhaust gas recirculation. Reducing EGR means the cylinders will need to contain less pressure, inviting modest performance and fuel economy improvements. Torque curves are improved, too. Schneider National Vice President of Purchasing Steve Duley notes that “the engine manufacturers have taken advantage of having injection pressure available at any time during or after the compression stroke. Drivers report better acceleration and quieter running engines… Drivers like the power and overall performance.” In Cummins’ case, the reduction in the amount of air plus exhaust needed is compounded by the adoption of the new XPI, high- pressure common rail injection system for 2010. Unlike unit 34 OVERDRIVE MARCH 2011 performance T Manufacturers say EPA-driven changes yield better fuel economy and other benefits. BY JOHN BAXTER injectors, the common-rail system provides whatever injection pressure is needed even at low rpm. “With the rocker actuation of injectors in the past,” says Zack Ellison, Cummins’ technical director of customer support, “we had to tune the rocker lever for system performance in a way that gave less than optimum performance at low rpm” because of reduced atomization. The result, says Ellison, is the ability to produce more torque at a lower rpm, and a more favorable torque curve, which “reduces the