Detroit Diesel put a different spin on the old idea of double turbocharging by linking the DD15's second, low-pressure turbo to the flywheel. Called turbocompounding, the concept captures extra exhaust energy to boost power and/or cut fuel use. The DD15 got Blue Tec exhaust-fluid aftertreatment that works with the existing particulate filter, existing exhaust-gas recirculation, and high-efficiency combustion to cut NOx emissions. The 2010 version also gets up to 5 percent better fuel economy, the company says.
