Fuso Launches First Truck DCT
Mitsubishi Fuso has become the world’s first commercial vehicle maker to launch a dual clutch transmission system for trucks. Developed as part of a new high-efficiency driveline also integrating the 3-liter 4P10 diesel engine and a Blue Tec DPF and DeNox aftertreatment system, the dual clutch transmission will initially be fitted to a new range of light truck models now in the final stages of development.
Mitsubishi Fuso Truck and Bus Corporation, 85 percent owned by Daimler of Germany, is one of Asia’s leading commercial vehicle makers. In 2009, MFTBC sold almost 100,000 light, medium and heavy trucks and buses.
Labeled DUONIC, the new MO3856 transmission has six speeds and uses twin concentric wet clutches located in the bell housing at the front of the casing. Mitsubishi Fuso describes it as an automated manual transmission and, as with car segment DCTs, the stated aim of the design is to maximize power transmission efficiency and to provide the smooth driving comfort of an automatic. The two-pedal design was developed in-house, as were the control programs. Component manufacture and assembly will also take place in-house.
The control system incorporates fuzzy logic, which Mitsubishi pioneered in the car segment in the 1990s. In the truck application, it takes account of vehicle load, road conditions and throttle pedal pressure to provide the optimum gearshift strategy and to exploit to the maximum the DCT’s unique feature of torque interrupt-free shifts. An ECO mode triggers earlier upshifts, benefiting from the fact that the truck does not lose momentum between gears when climbing hills.
Thanks to the wet clutch design, says Mitsubishi, regular clutch plate replacement is no longer necessary. This reduces servicing costs and eliminates unnecessary downtime in the service bay. The wet clutch design also allows a creep function to aid maneuvering and city center driving, as well as easing hill starts. The transmission incorporates an internal parking lock function, just as on a planetary automatic.
The new four cylinder, 16-valve engine makes the move to piezo injectors for its common rail fueling system. It is claimed to be lighter than its predecessor and, although Fuso has not yet disclosed power or torque outputs, the company says that the combination of the new engine, the emission control system and the DUONIC dual clutch transmission results in overall fuel consumption savings of between 8 and 10 percent, compared to the outgoing power train. The new power train will comply with Japan’s tough 2010 Long Term Emissions Regulations, as well as upcoming standards for Europe and the U.S.
Mitsubishi Fuso has the lead role within the Daimler group when it comes to developing light trucks, and says that the new power train will serve as the “powerful and efficient heart” of the company’s upcoming generation of light-duty trucks. No statement has yet been made in relation to any possible broadening of the DUONIC’s applications beyond the Japan-sourced Fuso and Canter light truck ranges. However, Europe is a highly CO2-conscious market and Daimler’s successful German Sprinter series shares a similar rear drive mechanical configuration. It would appear an astute move for Daimler to boost its light truck position by leveraging the fuel (and CO2) savings that this DCT transmission can provide.
| 4P10 Engine Specifications | |
|---|---|
| Engine Model | 4P10 |
| Cylinders | In-line four |
| Air Intake Method | Intercooler Turbo |
| Bore x Stroke (mm) | 95.8 x 104 |
| Total Displacement (cc) | 2.998 |
| Power, Torque | Not disclosed |
| DUONIC Dual Clutch Transmission Specifications | |
|---|---|
| Transmission Model | M038S6 |
| Clutch | Dual Wet Clutch |
| Number of Gears | Forward: 6 Reverse: 1 |
Story Filed: 10/02/2010
By Tony Lewin, managing editor DCTfacts.com