A direct-shift gearbox/DSG or dual-clutch transmission/DCT, as its name suggests, utilises two separate clutches in place of a singular item to transmit torque further along the vehicle's driveline. It is essentially two clutches and two gearboxes in one car.
While the concept of a dual-clutch transmission dates back to the early 1900s, it wasn't until the 1980s that significant advancements in electronic management allowed working examples and racing applications to be produced. The first clutch is responsible for controlling gears 1/3/5 and the second clutch looks after gears 2/4/6 and reverse. This mechanism provides smooth shifting similar to an automatic transmission but the efficiency of a manual transmission. The TCM (Transmission Control Module) determines which gear is selected.
Dual-clutch transmissions are becoming increasingly popular, and are available in a wide range of passenger and sports vehicles from carmakers such as VW, Audi, Ford, Renault, Kia and Hyundai. DSG's can be found in anything from small compact passenger cars and motorcycles to hyper cars like the Bugatti Veyron and even larger commercial applications. What’s more, a large number of today's vehicles are selling this concept as a new high-tech feature.
Dual-clutch transmissions are fully automated as opposed to manual transmissions, so there is no clutch pedal. The main difference between these and conventional automatic transmissions is that the two clutches are used in place of a torque convertor. Unlike traditional transmissions, which use singular first motion shafts, a DCT has two concentrically arranged input shafts. These inner and outer input shafts are used to control drive to either odd or even gear sets (for example 1st, 3rd, 5th, or 2nd, 4th, 6th gears).
When driving, one gearset is engaged and delivering torque through the driveline, while the next gear ratio on the alternate set is preselected and ready for use. This preselection of ratios reduces the time required to engage the next gear and in turn, improves efficiency in the driving experience.
DSG transmissions are quicker to shift because the powertrain never gets disconnected from the transmission in contrast with manual or automatic transmissions. This process allows for faster gear changes; as a result, drivers experience improved acceleration.
Compared to most traditional automatic or manual transmissions, DSG transmissions offer better fuel economy since they don't employ a torque convertor.
When installing DSG clutch kits is essential to use the right tools. They are specific and expensive due to their superior quality and comprehensive features. EXEDY offers the free use of the toolset when you purchase a DSG clutch from EXEDY.
When fitting a DSG clutch, another important consideration is the dual-mass flywheel. Our recommendation is to always replace the dual-mass flywheel at the time the DSG clutch is replaced. The dual-mass flywheel fitting may vary from vehicle to vehicle, so we suggest to consider the engine code and its torque output, as well as the number of teeth on the rim gear.
EXEDY offers replacement clutch kits and flywheels for the most common Direct Shift Gearboxes (DSG). Specialised tool boxes for clutch replacement are available for loan with DSG clutch kits purchases. Subject to availability, terms and conditions apply. Please visit www.exedy.com.au for further details.
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