Direct-shift gearbox

A direct-shift gearbox (German: Direkt-Schalt-Getriebe), commonly abbreviated to DSG, is an electronically controlled dual-clutch multiple-shaft manual gearbox, in a transaxle design – without a conventional clutch pedal, and with full automatic, or semi-manual control. The first actual dual-clutch transmissions derived from Porsche in-house development for 962 racing cars in the 1980s.

In simple terms, a DSG is two separate manual gearboxes (and clutches), contained within one housing, and working as one unit. It was designed by BorgWarner, and is licensed to the Volkswagen Group, with support by IAV GmbH. By using two independent clutches, a DSG can achieve faster shift times, and eliminates the torque converter of a conventional epicyclic automatic transmission.

At the time of launch in 2003 - it became the world's first dual clutch transmission in a series production car, in the German-market Volkswagen Golf Mk4 R32 and shortly afterwards, worldwide in the original Audi TT 3.2; and for the first few years of production, this original DSG transmission was only available in transversely orientedfront-engine, front-wheel-drive — or Haldex Traction-based four-wheel-drive vehicle layouts.

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