Although this S tronic gearbox is being marketed under the same name as the Borg-Warner-developed, six-speed twin-clutch transmission (previously known as the Direct Shift Gearbox, or DSG) in the U.S.-spec Audi A3 and Audi TT, it's a completely different unit. Parent company Volkswagen AG engineered it in-house and it will be built at VW's factory in Kassell, Germany. Cooling is significantly improved on the new S tronic, thanks to a vacuum booster that effectively doubles the amount of oil available to lubricate the twin clutches, and this helps the transmission cope with higher engine torque loads — up to 406 pound-feet (550 Nm), says Audi. The older S tronic transmission tops at 258 lb-ft (350 Nm). Moreover, because the clutches and oil pump are oiled separately from the gearsets and differentials, this S tronic gearbox can be more easily packaged with the longitudinal engine layouts used in most Audis, including the new Q5 and the A4, A5, A6 and A8 families.
Along with this packaging flexibility, the new dual-clutch transmission is designed to satisfy a wide range of driving situations. In the 2009 Audi Q5s we drove in Valencia, Spain, the S tronic was nearly as smooth as the best of today's conventional automatic transmissions in normal traffic, while offering much sharper response during more aggressive maneuvers. Shift paddles at the nine-and-three positions on the steering wheel allow you to call up your own shifts. Depending on the urgency of your throttle and brake inputs, downshifts requested in manual mode are rev-matched. Equally important, the transmission's large number of gear ratios make it as good a match for the 3.2-liter gasoline V6 we'll see in U.S.-market Q5s as it is for the Europe-only 3.0-liter turbodiesel V6 (3.0 TDI).
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