Mitsubishi Motors Corporation is the latest automaker to announce a twin clutch automated manual transmission, adding a choice of operating modes for different driving situations.


It will appear in the redesigned Lancer Evolution due for launch this autumn along with an updated version of the S-AWC (super all wheel control) vehicle dynamics control system that regulates drive torque at each wheel already used in current Evolution models.


The Japanese automaker is branding its new gearbox Twin Clutch SST (SPORT shift transmission) and described it as “an automated manual transmission that delivers slicker shifting through the gears while freeing the driver from the need to operate the clutch” at an announcement event in Tokyo on Tuesday morning.


Mitsubishi Motors Europe spokesman Daniel Nacass told just-auto that the transmission is not the Borg-Warner unit, best known branded as DSG (direct shift gearbox) in Volkswagen group vehicles.


He stressed that it was not uniquely developed by Mitsubishi but said the automaker had worked closely with a supplier, which he could not name at this stage. He also would not say whether the supplier was Japanese or not.


Earlier, in Japan, Mitsubishi said its new twin clutch SST and S-AWC make driving more intuitive by working to efficiently distribute power appropriate to road conditions, and deliver outstanding control and stability maintained by an ‘intelligent’ system that reads and reflects driver intent in real time.


The updated S-AWC system now adds active stability control feature to the active centre differential, active yaw control and sport antilock brake system components already proven in earlier Lancer Evolution series. Integrated system management of these four components allows regulation of torque and braking force at each wheel. S-AWC also now employs yaw rate feedback control which allows the system to control each wheel under a wide range of driving conditions.


MMC said the new automated manual transmission employs dual clutches to achieve power transmission efficiencies on a par with a normal manual gearbox while also allowing slick and swift shifting. It also returns superior fuel economy thanks to its high-efficiency power transmission mechanism.


The new transmission also features three operating modes tailored to different situations: “from around-town drivability to instant-response and follow-the-line sporty motoring on the open road,” according to the automaker.


Similar to the BorgWarner unit, the new twin clutch SST puts odd (1st, 3rd, 5th) and even (2nd, 4th and 6th) gears on separate input shafts, each connected to an individual clutch. With both clutches under precise system control, this arrangement allows lightening-fast, smooth and lag-free gear changes with no interruption in power delivery. Using clutches instead of a torque converter to transmit power makes the transmission simpler in structure and reduces power transmission losses for higher transmission efficiency that leads to improved fuel economy, according to MMC.


The three shifting programmes – Normal, Sport and S-Sport – cover the full range of driving situations, from town use to open roads.


For use around town and other normal driving situations, Normal mode scheduling uses relatively low-speed shift points to deliver unobtrusive shifting for maximum comfort together with optimum fuel economy.


For use when driving in the mountains or when engine braking is required, Sport mode scheduling uses higher shift points and quicker shifting to deliver instant throttle response.


Compared with Sport mode, S-Sport mode scheduling keeps the engine turning at higher revs while allowing lightening-fast shifting.