Mitsubishi Fuso Truck of America, Inc. has unveiled a new, highly evolved powertrain for the next generation of Mitsubishi Fuso Class 3-5 trucks in North America.

The integrated powertrain meets EPA 2010 emissions standards, improves drivability, and is expected to increase fuel economy by well over 10 percent compared to the '07 4M50-model engine, the company says.

4P10 Engine

The heart of the powertrain is the new three-liter, in-line four-cylinder diesel 4P10 engine. It features an intercooled, two-stage turbocharger, piezo-type fuel injectors, common-rail injection system, dual overhead cams, and a lightweight block. Careful tuning and higher-revolution operation, combined with the rapid response of the piezo fuel injectors, provides a flat torque curve with smooth, responsive operation.

DUONIC Dual-clutch Automated Transmission

New for 2011-- and the result of a 30-year development effort -- is the Duonic dual-clutch transmission. It's a 6-speed gearbox that works in-sync with the new engine to meet the company's drivability, emissions, and fuel efficiency goals. It's an easy-to-operate, two-pedal affair that blends the ease of operation of an automatic with the performance and fuel economy of a manual transmission.

The transmission's electronic control system uses a multi-value control system to match transmission shift points to vehicle load, speed, driving conditions and accelerator angle. This minimizes torque interruption during gear changes, so shifts occur smoothly without power loss, the company claims. It's programmed to optimize gear selection for maximum fuel savings while maintaining power delivery to the drive wheels.

The transmission also features an "ECO mode" allowing the driver to adjust shift points to reduce fuel consumption during heavy traffic operation. A "creep" function has been added to make control of the vehicle easier when subtle adjustments to vehicle speed are needed in heavy stop-and-go traffic and for hill starts. For added convenience, and as with most automatic transmissions, a Park function has also been included, which locks an internal transmission gear to help assure safety and stability when the vehicle is parked.

The DUONIC transmission uses a wet-clutch design to minimize clutch wear, and reduce maintenance costs.

BlueTec Emissions Control

Mitsubishi Fuso brought forward and enhanced its EGR solution from EPA 2007, and has added Daimler AG's BlueTec selective catalytic reduction (SCR) aftertreatment to meet EPA 2010. The SCR system consists of a catalyst and diesel exhaust fluid (DEF) tank, a DEF doser, and a control module. DEF consumption is expected to be about 2 to 3 percent of the vehicle's fuel consumption rate, under most common operating conditions, claims Mitsubishi Fuso.

Proven and Reliable

The new powertrain has undergone durability testing accumulating nearly 2 million miles in Asia, Europe and the United States. In addition, the 4P10 engine and BlueTec system are already installed in selected Mitsubishi Fuso trucks operating in Europe, and have recently been introduced into Mitsubishi Fuso's product line in Japan.

More info: Mitsubishi Fuso Truck of America.