Twin Clutch SST (Sport- or Sportronic Shift Transmission) is the
brand name
A brand is a name, term, design, symbol or any other feature that distinguishes one seller's good or service from those of other sellers. Brands are used in business, marketing, and advertising for recognition and, importantly, to create an ...
Getrag
Getrag (), stylized as GETRAG, was a major supplier of transmission systems for passenger cars and commercial vehicles. The company was founded on 1 May 1935, in Ludwigsburg, Germany, by Hermann Hagenmeyer; as the ''Getriebe und Zahnradfabrik ...
for
Mitsubishi Motors
is a Japanese multinational automobile manufacturer headquartered in Minato, Tokyo, Japan."SS-T: The Magic Inside the Evo X" ''The Motor Report'', April 14, 2008 The system was first incorporated in the 2008 Lancer Evolution X, and was designed to be a more performance-oriented system than that developed by rival manufacturers,"Technical Analysis: Twin-Clutch Sportronic Shift Transmission" Shaun Bailey, ''
Road & Track
''Road & Track'' (stylized as ''R&T'') is an American automotive enthusiast magazine. It is owned by Hearst Magazines and is published 6 times per year. The editorial offices are located in New York, New York.
History
''Road & Track'' (often ...
, March 2008 with shorter gear ratios optimized for acceleration."2008 Mitsubishi Lancer Evo MR: TC-SST Gearing" Brent Romans, ''
Inside Line
Edmunds.com Inc. (stylized as edmunds) is an American online resource for automotive inventory and information, including expert car reviews based on testing at the company's private facility. The company is headquartered in Santa Monica, Califor ...
'', August 21, 2008
Operation
TC-SST uses dual-
clutch
A clutch is a mechanical device that engages and disengages power transmission, especially from a drive shaft to a driven shaft. In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). ...
es to change gears. The TC-SST completes the clutch and gear shifts more quickly than a driver could in a conventional
manual transmission
A manual transmission (MT), also known as manual gearbox, standard transmission (in Canada, the United Kingdom, and the United States), or stick shift (in the United States), is a multi-speed motor vehicle transmission (mechanics), transmission ...
, and is also quicker than either an
automatic transmission
An automatic transmission (sometimes abbreviated to auto or AT) is a multi-speed transmission used in internal combustion engine-based motor vehicles that does not require any input from the driver to change forward gears under normal driving ...
with a
torque converter
A torque converter is a type of fluid coupling that transfers rotating power from a prime mover, like an internal combustion engine, to a rotating driven load. In a vehicle with an automatic transmission, the torque converter connects the p ...
, or a single-clutch
automated manual transmission
The automated manual transmission (AMT) is a type of transmission for motor vehicles. It is essentially a conventional manual transmission but uses automatic actuation to operate the clutch and/or shift between gears.
Many early versions of ...
. The system's high-efficiency power transmission mechanism is on par with a normal manual gearbox while allowing quicker
gear shift
A gear stick (rarely spelled ''gearstick''), gear lever (both UK English), gearshift or shifter (both U.S. English), more formally known as a transmission lever, is a metal lever attached to the transmission of an automobile. The term ''gear s ...
ing with no drop-off in engine power, thus offering greater
performance
A performance is an act of staging or presenting a play, concert, or other form of entertainment. It is also defined as the action or process of carrying out or accomplishing an action, task, or function.
Management science
In the work place ...
and better fuel economy. The system can be operated by both a console-mounted shifter and
magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ...
steering wheel
A steering wheel (also called a driving wheel (UK), a hand wheel, or simply wheel) is a type of steering control in vehicles.
Steering wheels are used in most modern land vehicles, including all mass-production automobiles, buses, light an ...
paddle shifters; and offers semi-manual and fully automatic modes. TC-SST also works in conjunction with Mitsubishi's
S-AWC
S-AWC (Super All Wheel Control) is the brand name of an advanced full-time four-wheel drive system developed by Mitsubishi Motors. The technology, specifically developed for the new 2007 Lancer Evolution,
system."Mitsubishi Motors' S-AWC Integrally Controls Vehicle Behaviors with 2 ECUs" Naoshige Shimizu, Nikkei Electronics, July 11, 2007
The operation of TC-SST is smoother than that of a conventional automatic transmission because it uses clutches instead of a
torque converter
A torque converter is a type of fluid coupling that transfers rotating power from a prime mover, like an internal combustion engine, to a rotating driven load. In a vehicle with an automatic transmission, the torque converter connects the p ...
to transmit power. The key to the system's operation is in the electronic and
hydraulic
Hydraulics (from Greek: Υδραυλική) is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counte ...
controls. TC-SST can select two gears at the same time by putting odd (1st, 3rd, 5th) and even (2nd, 4th, and 6th) gears on separate input shafts, each connected to an individual clutch. While one gear is engaged by one of the two electro-hydraulically operated wet multi-plate clutches, the other is pre-selected, waiting to be engaged by the second wet multi-plate clutch. The TC-SST, in principle, behaves like two three-speed manual transmissions operating on the same output shaft. With both clutches under precise system control, the gear change is made when the clutches are "swapped" simultaneously, allowing fast, smooth gear changes with no interruption in power delivery. Nevertheless, those who prefer the traditional "
stick shift
A manual transmission (MT), also known as manual gearbox, standard transmission (in Canada, the United Kingdom, and the United States), or stick shift (in the United States), is a multi-speed motor vehicle transmission system, where gear changes ...
" have criticized the level of driver involvement in TC-SST and other dual-clutch transmissions."Stop this twin-clutch madness now" John McIlroy, '' Autocar'', April 8, 2008
The odd and even gear shafts are linked via a transfer gear, resulting in a shorter overall transmission length. The transmission
electronic control unit
An electronic control unit (ECU), also known as an electronic control module (ECM), is an embedded system in automotive electronics that controls one or more of the electrical systems or subsystems in a car or other motor vehicle.
Modern vehic ...
(ECU), sensors, and solenoids, are all housed within the transmission valve body. The TC-SST is equipped with a transmission oil-cooler, and uses a synthetic fluid, designed for twin-clutch transmissions (see owner's manual).
Drive modes
TC-SST allows switching between three shifting programmes: "Normal", which uses relatively low engine-speed shift points to deliver conservative shifting biased towards optimized fuel economy;"Mitsubishi Lancer RalliArt – Twin Clutch SST Transmission" MPG-o-matic "Sport", for use when driving in the mountains or when engine braking is required;"Mitsubishi releases details on S-AWC and Twin Clutch SST" Damon Lavrinc, Autoblog.com, July 10, 2007 and "S-Sport", which keeps the engine turning at even higher revs compared to "Sport"."Mitsubishi reveals Twin Clutch SST gearbox" Paultan.org, July 10, 2007 " Launch control" is also available only in "S-Sport" mode.
Note: "S-Sport" is only available from the factory on Evolution X MR editions and not on the TC-SST found in current Lancer Ralliart, which makes do with Normal and Sport modes. Towards the end of 2012, however, aftermarket car tuners figured out how to successfully flash/reflash (see Chip tuning for details) the Lancer Ralliart's Transmission control unit with the Evolution X MR's transmission software, giving the Lancer Ralliart "S-Sport mode", which includes higher RPM engine operation and launch control. Debate still exists, however, regarding whether or not the different 5th and 6th gear ratios found in the Ralliart transmission (when compared to the Evo X MR TC-SST, see gear ratios below) adds extra mechanical stress to an "S-Sport Mode" flashed Ralliart Transmission.
Inside Line
Edmunds.com Inc. (stylized as edmunds) is an American online resource for automotive inventory and information, including expert car reviews based on testing at the company's private facility. The company is headquartered in Santa Monica, Califor ...
Mitsubishi Lancer Evolution X
The Mitsubishi Lancer Evolution X is the tenth and final generation of the Lancer Evolution, a sports sedan produced by Japanese manufacturer Mitsubishi Motors.
By September 2005, Mitsubishi introduced a concept version of the next-gen Evolution ...
Citroën C-Crosser
The Citroën C-Crosser is a compact crossover SUV launched in July 2007, designed for the French manufacturer Citroën, and produced by Mitsubishi on the basis of the Outlander. The equivalent Peugeot badge engineered version was the 4007.
It w ...