Twin Clutch SST (Twin Clutch Sport Shift Transmission)

The corporate philosophy of Mitsubishi Motors includes "Driving Pleasure," "Toughness & Safety" and "Environmental Responsibility." We created the Twin Clutch SST with the goal of realizing these philosophies at a very high level.

Twin Clutch SST

Twin Clutch SST

The Twin Clutch SST is an automated manual transmission that provides gear shifting more responsive than a normal manual transmission without the need for manual clutch and shift change operation. It combines the economy and fun of a manual transmission with the easy drive of an automatic transmission.

Basic Structure

The Twin Clutch SST made a quick gearshift with no gearshift time lag possible by switching alternately between two clutch sets, the clutch for the odd numbered gears (1st, 3rd, and 5th gears) and the clutch for the even numbered gears (2nd, 4th, and 6th gears). Furthermore, the power is transmitted by the clutch not a torque converter so the structure is simple, the power loss is very small, and the transmission efficiency is outstanding, resulting in an improvement in fuel economy as well.

Twin Clutch SST Structure Diagram

Twin Clutch SST Structure Diagram

Benefits

Using the twin clutch method for the automated manual transmission enabled a "good acceleration feeling" due to the quick gearshift and an "outstanding fuel economy performance" due to the highly efficient power transmission mechanism.
Moreover, because we incorporated three shifting programs tailored to different driving situations, the transmission can handle a wide range of driving challenges from city driving to driving on winding roads.

Fuel Economy(10-15 Mode Fuel Economy)
Acceleration from Rest Performance

Drive Modes

Twin Clutch SST allows the driver to switch between three shifting programs -Normal, Sport and S-Sport- to cover the full range of driving situations, from town use to sporty motoring on open roads.

(1) Normal mode

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.

(2) Sport mode

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 that instills in the driver a closer man/machine relationship.

(3) S-Sport mode (only installed in the Lancer Evolution X)

Compared with Sport mode, S-Sport mode keeps the engine speed at higher revs and allows faster shifting.