And broken record time again… Not for the US market for some unknown reason?
Wayne Gerdes – CleanMPG
– Sept. 25, 2008
2008 European Dodge Journey includes an optional 2.0L turbo diesel engine with 140 HP and 229 lb.-ft. of Torque. With the standard six-speed manual transmission, the diesel achieves 36mpgUS combined on the European NEDC. The same 2.0L with the all-new six-speed dual-clutch automatic transmission achieves 33.6 mpgUS on the same NEDC. Imagine that. A small Chrysler SUV with the same fuel economy as the Toyota Yaris in the US.
Auburn Hills, MI - Chrysler expanded the number of vehicles equipped with a new fuel-saving dual-clutch automatic transmission. In addition to the current European Dodge Journey, the European Dodge Avenger and Chrysler Sebring, powered by a 2.0L turbo-diesel engine, will also receive the new transmission technology. Chrysler and Gertrag’s new dual-clutch transmission provides a fuel economy improvement of 6 percent compared to a traditional four-speed automatic transmission.
“Chrysler’s new dual-clutch transmission is the next step in transmission technology, offering consumers improved fuel economy along with smooth shifting,” said Frank Klegon, Executive Vice President – Product Development, Chrysler LLC. “This important new Chrysler technology is one of several initiatives we have in place to directly focus on improving fuel efficiency across our vehicle lineup.”
Dual-clutch Transmission Technology
Chrysler’s dual-clutch automatic transmission technology improves fuel economy by reducing parasitic losses similar to the way a manual transmission operates. First by eliminating the torque converter, and second, through the use of synchronizers instead of shift clutches.
The dual-clutch transmission is an automatic transmission that utilizes dual launch and shift clutches with a manual transmission style lay-shaft gear arrangement instead of a conventional torque converter and planetary gears. One clutch drives the odd-numbered gears and reverse, while the other clutch drives the even-numbered gears. During shifts, the next gear is anticipated and pre-selected. Then one clutch is opened while the other is closed, allowing shifting without torque interruption. Further, with the lay-shaft arrangement of gears, there is increased flexibility to optimize gear ratio selection for performance and fuel economy.
The all-new dual-clutch transmission does not require a torque converter to transfer engine torque to the transmission. Instead, it uses two wet multi-plate clutches. With the wet multi-plate clutch system, the clutch components are bathed in lubricating and cooling fluid in order to provide adequate thermal capacity.
The wet multi-plate clutch system uses hydraulic pressure to actuate the clutches and provide for gear selection. With this system, the power flow from the engine to the transmission is not interrupted during a shift, resulting in a power-on shift. This means that there is less torque disturbance than a conventional planetary automatic transmission with torque converter. Also, by eliminating the torque converter and reducing the number of shift clutches, parasitic losses are reduced, leading to improved fuel economy.
When will the same fuel saving transmission technology as well as the very fuel efficient 2.0L turbo-diesel be available in the US? Unknown