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Current production of Dual Clutch Transmissions (DCTs) feature a maximum of seven speeds, which can easily be realized using three main shafts and four shift sleeves. To increase the number of gears with conventional means, more gears, shift sleeves and shafts have to be added thus increasing size, weight and cost. With the “xDCT” family, FEV has developed a series of DCT concepts which effectively minimize mechanical complexity for any given number of gears by combining two innovative ideas: “Gear generation” and “supported shifts”. In order to “generate gears”, a switchable connection between the two input shafts is installed which allows to use all gears inside the transmission with both clutches. The main challenge then is to effectively use the large number of resulting gears in a shift schedule without torque interruption. The solution is to incorporate “supported shifts” during which torque fill-in for an AMT-style gear shift is provided by the next higher gear.