Volkswagen’s Direct Shift Gearbox (DSG) is the world’s first dual-clutch automated manual gearbox in a production car. This provides the driver the ease-of-drive of a car equipped with an automatic transmission, but the efficiency and flexibility of a manual transmission.
It’s like a far more advanced big brother of automated manual transmissions like the one found in the Proton Savvy AMT. Something like BMW’s SMG, but Volkswagen’s DSG was the first to have dual clutches. Volkswagen’s DSG transmission also has a triptronic function, allowing gears to be manually selected as well as an automatic mode.
A conventional manual gearbox has a human foot-operated single clutch. A DSG transmission has two clutches, one for the even gears and one for the odd gears plus the reverse gear. One clutch is in gear, while the other pre-selects the next gear. This allows really fast shifts, no more than three to four hundredths of a second. For example, if the car is in third gear, the other clutch already has fourth gear selected but is not active. As soon as the RPM reaches the ideal shift point for the car’s torque curve, the gearbox shifts into fourth gear almost instantly.
Here’s a video with a drag race comparison between a Volkswagen Golf GTI 6-speed manual and a Volkswagen Golf GTI equipped with a 6-speed DSG gearbox. The Volkswagen Golf GTI with the DSG gearbox is also pitched against other cars with conventional gearboxes but with better power to weight ratio than the Volkswagen Golf GTI. You’ll be able to see how the DSG fares.
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