• Audi's DSG (Direct shift gearbox) have been used for the first time in TT3.2 Quattro. 
  • DSG is actually another brand name for DCT. 
  • This gearbox combines the advantages of a conventional 6 speed manual gearbox and the qualities of a modern automatic transmission. 
  • It uses a twin multiplate clutch with ingenious electro hydraulic control so that the two gears can be engaged simultaneously. 
  • During dynamic operation of the car, one gear is engaged. 
  • When the next gear shift point is approached, the appropriate gear is preselected, but its clutch is kept disengaged. 
  • The gear shift operation opens the clutch of the activated gear and closes the other clutch at the same time with some overlap. 
  • Thus gear change is achieved under the load and maintaining continuity of the power flow. 
  • The control electronics ensures that gear shift is lightning fast, smoother and jolt free, eliminating loss of pulling power during up shifts. 
  • The manual and the automatic modes can be selected.



  • DSG gearbox is controlled by a computer which monitors many cars  sensors that is the rpm, speed, angle of steering input, amount of wheel spin, braking and G Forces. 
  • It can than use this inputs to make decisions as to in which gear the car has to be at any instant. 
  • For example, if you are approaching a shark curve you may want to change down two or even three gears. 
  • The computer sees that you are braking heavily, simultaneously operating the steering it than sends signals to change the gear down more quickly or skip gears altogether. 
  • This keeps the car in the best range for drivability. 
  • Similarly in case of snow or mud, the computer sees the heavy wheel spin at low speeds and can than shift up into a higher gear so as to control the wheel spin.

The advantages of DSG are :-

1. Smooth gear changing and harmonious acceleration without any interruption in the power flow.

2. Low fuel consumption.

3. Convenient operation.

The only disadvantage is delay in suddenly downshifting two steps, example from fourth gear to second gear, which can take about 900 milliseconds compared to 300 milliseconds for a regular shifting, which, of course, is not bad in comparison to conventional transmission.