DSG gearbox is a family of dual-clutch transmissions used by several car manufacturers under the VW group. DSG stands for Direct Shift Transmission or Direkt-Schalt-Getriebe in German. It consists of two manual gearboxes built into one that is electronically controlled.
Due to the unique way it operates, DSG combines the best attributes of both the manual gearbox and automatic gearbox providing performance and efficiency. It can be operated in a fully automatic mode, where the computer decides when and how to shift, or in a semi-automatic mode, where the driver uses either the gearshift shift lever or steering wheel-mounted paddles to select the desired gear.
Read: Guide To Toyota Models Trim Levels
How does it work?
Cars with automatic transmission do not have a clutch for transmitting power to the wheels like cars with manual transmissions. They, instead, have a torque convertor. So like a manual gearbox, DSG gearbox uses a clutch; but unlike a manual gearbox, the clutch in a DSG gearbox is actually two clutches that are electronically controlled.
One clutch is for odd-numbered gears and the other clutch for even-numbered gears. Each clutch operates independently for smooth and quick shifting without the need of a clutch pedal. When one clutch is transmitting power to the wheels, the gearbox determines which gear will be needed next and uses the second clutch to get it ready. When its time to change, the gearbox simply disengages one clutch and engages the other.
Some of the factors that the onboard computer uses to determine the next gear to engage include driving mode, engine and road speeds.
Advantages of DSG gearbox
- Gear shifts are smooth, seamless and very fast. Some manufacturers are claiming a time less than four-hundredths of a second.
- They make cars fuel efficient.
- They are low maintenance.
Disadvantages of DSG gearbox
- Although failures are rare, when they do occur are expensive to fix.
- Incorrect shifts can lead to loss of power, hesitation and unpredictable driving.
- Cars with DSG gearbox are comparatively expensive than counterparts with automatic or manual transmission.
Some of the brands under the VW group that uses DSG gearbox for their cars include VW, Audi, Lamborghini, Bentley, Seat and Skoda. Porsche also uses DSG gearbox under the name PDK (Porsche-Doppelkupplungsgetriebe).
