With a press of the pedal, this car transmission can give a superior performance regardless of the engine size. Some of the car transmission like CVT and Torque Converter are installed to give a fuel efficiency but on the performance side, it is not as good as this transmission. This transmission had been fixed in many performances oriented sedan and sports cars like Porsche, Audi, Volkswagen, Mercedes-Benz AMG, McLaren, Ford Motors, Nissan GTR and much more. This transmission is also one of the most loved transmission by the car lovers maybe after ZF transmission and this is the Dual Clutch Transmission.

What is a Dual Clutch Transmission? A dual clutch transmission or sometimes can also be called or referred as Twin Clutch Transmission or Double Clutch Transmission have 2 separate clutches to control the odd number (1,3,5,7) and even number (2,4,6,8) gear sets. Both of this clutches in contained within one single gear housing and works as one unit. They can operate via an automatic shifting and also worked as semi-manual gear if the user had engaged in the S mode in the car gear indicator.

The invention of the Dual Clutch Transmission(DCT) is from a Frenchmen Adolphe Kegresse before the start of World War 2 but unfortunately, he never developed any prototype or working model. The working model and the first development of the DCT started in 1980 under the guidance of Harry Webster at Automotive product who had installed their built DCT prototype in Ford Fiesta MK1, Ford Rangers and Peugeot 205. The control of the gear was based on the pure analogue/ discrete digital circuit.

In late 1980, following a discussion with Volkswagen/Porsche, the DCT work continued for their in-house development especially for the Porsche and Audi racing cars and the control had been fully computerized compared to the previous analogue control. From this came the Porsche Doppelkupplungsgetriebe (PDK) is basically the name for Porsche car DCT gearbox. From here until now most of the DCT is computerized and this computer module called as Transmission Control Module(TCM).

A typical TCM in Ford Focus

One the main component in the DCT is the clutch where they are 2 type of clutches one is called as wet clutch and another called as a dry clutch. First the dry clutch is called in this term as they are less oil pumped in the system and this type clutch basically used in the car that has a small engines or lower torque where the wet clutch is designed in such a way that the oil is pumped constantly in the clutch that can be also defined as an oil bath for this type of clutches and this type of clutches is basically used more in the high-performance car or in the car that can produce high torque. In this wet type, the clutch was built for the high-performance car and in this case, the oil constantly needed to cool the gearbox down. On the reliability term, the wet clutch is far more reliable than the dry clutch. Remember that in 2012, Volkswagen Group Malaysia had encountered many complaints from the car owners with regards to their gearbox problem and most of this problem encountered by the user as the Volkswagen had used the dry clutch in their cars.

The are several car manufacturers who had installed DCT in their car model and will like to call it in a different name. First is Nissan Motors who had installed this DCT in their sports model Nissan GT-R. It is called as DCT GR 6 and it was created with the collaboration with BorgWarner and Nissan gearbox supplier Aichi Machine Industries. The transmission that had been built for Nissan GT-R able to hold up 810nm torque and having shift time of 150 milliseconds.

nissan gtr.jpg
Nissan GT-R DCT have one of the fast shifting gearboxes when they were invented before Volkswagen DSG had taken the spot.

Mercedez Benz also uses the DCT in their car model. With the exception of AMG model, most of the DCT is built by Mercedez Benz gearbox production. The DCT in AMG model was built by Getrag and called as AMG “Speed Shift” and it was mounted on the rear axle of the car with the shift time of 100 milliseconds.

AMG SelectShift Gearbox

The Ford Motors also had used the DCT in their car model previously. Named as PowerShift it is a wet clutch designed by Getrag too and Ford had installed this DCT in all of the models previously. Now due to some many unfortunate issues such jerking, delayed acceleration, transmission defect, and many issues that had led too inconvenient for the user it had been replaced it with a conventional automatic called as SelectShift.

The next car manufacturer that also the biggest user of the DCT and this transmission had always been associated with them. They are Volkswagen Group and they had named their DCT transmission as Direct Shift Gearbox or DSG. Their gearbox unlike Mercedez Benz, Nissan and Ford’s gearbox is fully built by BorgWarner. They are also had built the fastest shifting DCT in the industries where their DSG can shift up to 8 milliseconds. Quite a staggering number. The DSG is the name of DCT gearbox for the Volkswagen, Audi, Bugatti, Lamborghini and Skoda but for the Porsche it is called as Porsche Doppelkupplungsgetriebe (PDK). Standard across the Volkswagen group DSG the forward gearset speed is 7.

Volkswagen Group DSG gearbox 

The DCT invented by the Frenchmen before the World War 2 and had been developed by Harry Webster and continued production by Volkswagen Group had become one of the most loved transmission by the car lovers although the jerking issue, gearbox malfunction, and much more had led to inconvenience and dislikes of this gearbox for the car lovers. In China, they had demanded the Volkswagen Group to provide a 10-year warranty for the DSG gearbox warranties. In Malaysia, the Volkswagen Group had only provided 5 years’ warranties for this gearbox.

However, for all the issue one thing that can’t be denied is DCT provides a superior acceleration via a fast shifting from the odd number to even number and vice versa and it had been the choice for the car manufacturer in their high-performance sedan and sports car model. The Volkswagen Group had also planned to make 10 speed DSG but the plan had been dropped in late this year. With continuous improvements of DCT or DSG , it will be expected to be better than the current one.

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