Tag Archives: DSG

Volkswagen DSG Statistics

VW sells one millionth DSG, next million on the way

1 million DSG – Volkswagen celebrates the bestselling gearbox
Kassel has produced the dual-clutch gearbox for the Group since 2003
Latest 7-speed DSG now available

Wolfsburg/Kassel, 05 February 2008 – DSG – three letters that stand for supreme shift comfort, economy and sportiness. Together with staff from the Kassel factory and Prof. Werner Neubauer, member of the Board of Management of the Volkswagen brand responsible for the Components division, the management of the Volkswagen factory in Kassel today celebrated the one-millionth dual-clutch gearbox (DSG).

The idea for the dual-clutch gearbox was born in motor-racing. It was picked up by Volkswagen in the 1980s and has since been developed further. When the first Volkswagen DSG went into series production in 2003, it sent shockwaves through professional circles. This innovation provided a previously unknown level of shift comfort. The once clear line between automatic and manual gearboxes had been bridged, and an extraordinary level of driving dynamics achieved.

Even the customers were soon enthusing, despite all the reservation compared to conventional gearboxes. Just five years later, the DSG has, for example, a 25 percent installation rate on the Touran. This is also a major success for the staff at the Kassel factory, the only Volkswagen factory to produce the DSG.

In 2007 alone, more than 400,000 six-speed DSG gearboxes were installed across the Group – and there is no sign of an end to this success story. “Because of the great demand, we shall shortly be boosting our daily capacity to 1,750 units,” explained General Factory Manager Dr. Hans-Helmut Becker.

Prof. Werner Neubauer added: “All around the world, our DSG gearboxes from Kassel are synonymous with sporty driving pleasure and economical fuel consumption. They successfully combine the best of two gearbox worlds. We are already on the way to the two-millionth DSG, and on the way, this modern technology will sharpen Volkswagen’s global competitive edge in the field of transmission technology even further.”

Jürgen Stumpf, Chairman of the Works Council at the VW factory in Kassel is also convinced by the DSG: “The competence and expertise of our staff make this cutting edge technology ‘made by Kassel’ possible. The DSG has now become a guarantee for job security at the factory.”

Volkswagen has now shifted up a gear with the new 7-speed dual-clutch gearbox, the second generation of the successful bestseller. This gearbox combines two world firsts. Firstly, it is the first 7-speed DSG for front-traverse installation. Secondly, it is the first with clutches that are not immersed in oil, but which run “dry”. This enables the latest Volkswagen DSG, available in the Golf, Golf Plus, Cross Golf, Golf Variant, Polo, Cross Polo and other models to achieve even greater efficiency.

New 7 Speed DSG

28th January, 2008

Five years ago Volkswagen presented the first production dual-clutch transmission in the world: the 6-speed DSG. An intelligent automatic, a transmission of superlatives. The winning move of dual clutch transmissions had begun at Volkswagen.

Since then over one million 6-speed DSGs have been sold! In just the first eleven months of last year 364,000 were sold. This is now being followed up by another transmission sensation: the world’s first 7-speed DSG to be produced in high-volume. For many car drivers this could signify the final turn away from conventional transmissions. Because the new DSG can do everything better than a manual gearbox. It is more fuel efficient, sporty and comfortable.

DSG for the “small” high-volume engines
The new 7-speed DSG makes the revolutionary transmission technology available for smaller engines too, engines that develop up to 250 Newton-meter torque. The 7-speed DSG will be initially introduced on the Golf, Golf Variant and Golf Plus paired with the latest TSI (90 kW / 122 PS) and the bestselling TDI (77 kW / 105 PS) of the model series.

New “dry” dual clutch improves efficiency
The most prominent component of the DSG is its dual clutch. In comparison to the 6-speed DSG, there is no “wet” clutch in the new transmission that is a clutch immersed in an oil bath rather a “dry” clutch. That too is a world first for DSG technology. This and other engineering modifications led to significant improvements to the DSG’s efficiency. The result: Further reduced fuel consumption and emissions values, even greater convenience and driving fun.

The 122 PS TSI in the Golf consumes just 5.9 liters/100 km with DSG. A record
A look at the fuel economy and driving performance data of the Golf, with and without 7-speed DSG, underscores the progress made. This much can be said right away: The new 122-PS TSI on the Golf is a masterpiece of fuel efficiency. Shifted by a manual 6-speed gearbox, the charged gasoline engine in the Golf consumes just 6.3 liters of fuel per 100 kilometers and this is even less than that of models with lower PS output. However, when the same Golf TSI is paired with the new 7-speed DSG, average fuel consumption (95 ROZ octane Super) is reduced even further: to just 5.9 liters. Similarly, CO2 emissions are reduced from 149 g/km to 139 g/km. These are data that just a short while ago would have been considered inconceivable for a gasoline engine in this performance class. Especially for an automatic: Compared to a conventional automatic with torque converter, the new DSG even consumes up to 20 percent less fuel!

DSG market share up to 28 percent. Trend is upward
Since the 7-speed DSG can now also serve on smaller engines, another jump in volume can be expected for DSG. In the final months of 2007, the DSG share in the Golf class even without 7-speed DSG already rose to above nine percent. The year’s average for the new Golf Variant came in at over ten percent. On the Golf Plus the average for 2007 was greater than twelve percent. The Jetta had a DSG share of over 13 percent, and the Eos over 14 percent. 24 percent of all Touran buyers chose a dual-clutch transmission in the past year. It was about 22 percent on the Passat sedan and over 28 on the Passat Variant. The trend toward automatics when they have DSG is therefore clearly evident.

Before production start the new DSG covered two million test kilometers
Both DSGs are built at the VW Transmission Plant in Kassel. The light 70 kilogram 7-speed DSG is built with about 400 parts. The new transmission is like an old friend to employees in Kassel as production volume is being ramped up these days: as early as September 2005 a die-casting machine was used to produce the first prototype case. While the many DSGs had to prove their qualities on stationary test benches for far more than 60,000 hours of durability testing, developers sent the other DSG prototypes aboard Golf and Co. to run test trial routes in the real world. They covered about two million kilometers. Afterwards the findings were clear: the new DSG is extremely durable and extremely efficient too.

Pilot production started in November 2007 in Kassel
In the last week of November 2007, series production of the new DSG was finally started. Plans already call for increasing output up to 750 7-speed DSGs per day over the course of this year. If demand rises even more, production could be ramped up to 1,500 7-speed DSGs per day by implementing a second assembly line. In parallel, 1,500 units of the 6-speed DSG are being produced daily in Kassel. Demand is booming!

Facts and Figures

  • 0.4 liters fuel per 100 kilometers fuel savings on Golf TSI (122 PS) plus 7-speed DSG compared to identically powered counterpart with 6-speed manual transmission
  • 1.7 liters of oil are at work in the 7-speed DSG
  • 6 models can currently be ordered with 7-speed DSG
  • 6.5 liters of oil are at work in the 6-speed DSG
  • 70 kilograms is the weight of the 7-speed DSG
  • 93 kilograms is the weight of the 6-speed DSG
  • 105 PS is the power output of the currently “smallest” Volkswagen engine with DSG
  • 140 degrees (maximum) hot oil surrounds the control module (mechatronics) on the 6-speed DSG
  • 226 employees work in DSG production
  • 250 Newton-meter is the maximum torque of engines that are paired with Volkswagen’s 7-speed DSG
  • 300 PS is the power output of the currently “largest” Volkswagen engine with DSG
  • 350 Newton-meter is the maximum torque of engines that are paired with Volkswagen’s 6-speed DSG
  • 750 7-speed DSGs are already being produced every day at transmission plant in Kassel
  • 1,500 6-speed DSGs leave the Kassel transmission plant daily
  • 2003: first 6-speed DSG is introduced (on the Golf R32)
  • 2004: 6-speed DSG is used in combination with a turbodiesel for the first time (on Golf TDI and Touran TDI with 105 PS and 140 PS, respectively)
  • 2004: new Golf GTI offers a TSI paired with DSG for the first time
  • 2005: first Bugatti Veyron 16.4 with DSG is delivered
  • 2007: new Golf TSI with 122 PS and 7-speed DSG already places 2nd in Environmental Automobile List of the Verkehrsclub Deutschland (VCD; “German Travel Club”) for the compact class
  • 2007: Golf GT Sport with 170 PS strong TSI plus 6-speed DSG wins Technological Innovation of the Year award in Barcelona
  • 2007: at the end of this year series production was started for the 7-speed DSG
  • 2008: new Golf TSI with 122 PS and 7-speed DSG earns “Yellow Angel 2008? award by ADAC in “Innovation and Environment” category
  • 150,000 6-speed DSGs this DSG production milestone was surpassed at the Kassel transmission plant in 2005
  • 400,000 is the number of Volkswagens sold worldwide with DSG in 2007
  • 1,000,000 6-speed DSGs this DSG production milestone was surpassed at the Kassel transmission plant in 2007
  • 2,000,000 is the number of test kilometers covered by the 7-speed DSG over the course of its development

Volkswagen DSG – 7 Speed Dual Clutch Gearbox (High Output)

dsg_trans_7_speed__550nm_17 Speed DSG Gearbox (High Output)

Maximum Torque: 550 Nm

Orientation: Longitudinal & Quattro

The new Audi S tronic
Seven gears for dynamics and efficiency

* News high-tech transmission with twin-clutch technology
* Shifts at lightning speed with high efficiency
* Suitable for longitudinal installation and quattro drive

Seven gears that shift at lightning speed without interrupting traction – Audi presents a new phase in the evolution of transmission systems. The seven-speed S tronic combines its dynamic working method with high efficiency. The new twin-clutch transmission is designed to work with longitudinally installed engines and the quattro all-wheel drive system, and its 550 Nm torque capacity makes it suitable for a wide range of sporty models. Audi will introduce the new S tronic into multiple model lines in series production during the course of this year.

dsg_trans_7_speed__550nm_2With the seven-speed S tronic, Audi is launching a new phase in its drive strategy. The new transmission, which was developed entirely by Audi, is intended for the mid-range model lines. Audi has designed it to be sporty while also being a highly efficient high-tech component.

Audi drivers can use the new seven-speed S tronic in various modes. The fully automatic mode, in which the computer selects the gear, keeps the D (Drive) and S (Sport) programs available. The gears can also be manually switched with the shift selector lever or with the optional rocker switch on the steering wheel – an amazingly fast process.

The new high-tech transmission from Audi gives the driver a dynamic and comfortable sense of shifting with unsurpassed precision and perfection. It combines outstanding economy with superb agility and potential for sporty driving.

The seven-speed S tronic is composed of two transmission structures. It integrates two multidisk clutches that control different gears. The large K1 clutch located on the outside conducts the torque via a solid shaft to the gear wheels for the odd gears 1, 3, 5 and 7. They are located in the rear of the cast-aluminum transmission housing, toward the center of the vehicle.

A hollow shaft rotates around the solid shaft. It is connected to the smaller K2 clutch, which is integrated into the inside of its larger sibling, and which controls the gear wheels for the even gears 2, 4 and 6, as well as reverse gear. All gear wheels are located in a single row on both drive shafts, in the order 4, 6, 2, R, 1, 3, 7 and 5.

dsg_trans_7_speed__550nm_3Both transmission structures are continuously active, but only one is powered at a time by the engine. For example, when the driver accelerates in third gear, the fourth gear is already engaged in the second transmission structure – lying in wait, so to speak. The switching process takes place as the clutch shifts – while K1 is opening, K2 closes at lightning speed. This process takes only a few hundredths of a second and is completed without interrupting traction. It is so comfortable and smooth that the driver hardly notices it.

The power flows from the drive shaft to the self-locking center differential of the quattro drivetrain, which distributes it into two directions. In the basic distribution, 60 percent of the torque flows over the cardan shaft to the differential for the rear axle, and 40 percent flows over a side shaft to the bevel gear of the front-axle differential. Because this shaft is installed at a 7.2 degree angle, it uses a slanted, beveloid gear. To reduce weight, it is also hollow.

The asymmetric-dynamic power distribution provides sporty and agile driving characteristics with slight emphasis on the rear end. When needed, the center differential can deliver up to 85 percent of the power to the rear axle or a maximum of 65 percent of the power to the front axle.

Typical Audi: uncompromising quality

Each component of the new seven-gear S tronic attests to Audi’s innovative way of thinking and to the company’s uncompromising quality standards. Carbon-coated synchronizer rings ensure synchronization of unsurpassed quality and stability. The gears one through three and reverse are also designed as three-cone synchronizations.

dsg_trans_7_speed__550nm_4Highly precise management of both multidisk clutches was one of the most important development goals. This was achieved in part with a compact pressure cylinder, electronically controlled rotation speed compensation and the use of an optimized coil spring package. This package of technology provides maximum precision and comfort at startup and shifting.

The transmission is managed by the so-called mechatronic module. This module involves a compact group of control units and hydraulic control valves that is integrated on the left of the transmission when facing the direction of travel. Its control concept allows the speed of the gear shifting process to vary and extremely precise control of the power necessary for the process.

The required control pressure is provided by an efficiently operating oil pump that is located next to the mechatronic module and is driven by a gear section. The oil pump is supported by a vacuum booster for cooling the twin clutch during starting. This allows the amount of oil pumped to be roughly doubled as needed without increasing power.

A unique feature of the seven-speed S tronic is its two separate oil systems. While the twin clutch, mechatronic module and oil pump are supplied by their own oil circuit with seven liters of automatic transmission fluid (ATF) oil, the wheelsets and the central and front-axle differential are lubricated with about 4.5 liters of hypoid gear oil. This separation allowed the development engineers to position all of the components ideally, without being forced to compromise by using a single lubricant.

Audi has designed the new seven-gear S tronic to provide both exhilarating driving and consistent economy. The new high-tech engine is notable for its very high efficiency. Its highly intelligent controls also allow economical driving in automatic mode. The maximum possible transmission-ratio spread of 8.0:1 allows a sporty, short transmission ratio for the first gear as well as an rpm-sinking, long ratio for the last gear. The seven-speed S tronic is designed for up to 9,000 rpm and can transmit torque of up to 55 Nm.

Vorsprung durch Technik: the history of S tronic

Audi has led the march in the field of transmissions for many years. The introduction of quattro all-wheel drive in 1980 was a milestone in the history of automotive technology. And the S tronic is a prime example of the company’s basic philosophy – “Vorsprung durch Technik.”

dsg_trans_7_speed__550nm_5The first Audi with a twin-clutch transmission was produced way back in November 1985 – the Sport quattro S1, which was driven by Walter Röhrl and his copilot Christian Geistdörfer in the World Rally Championships. Röhrl, the finest rally pilot of his time, described his 350 kW (476 hp) sports car as “a formidable thing” and a “natural phenomenon” – and the high-tech transmission provided him with even more powerful performance.

The twin-clutch transmission, which was controlled electrically with a short touch control lever in the S1, could shift through its five gears at lightning speed. Because the traction was not interrupted, the turbocharger for the five-cylinder engine remained constantly pressurized – a bypass in the engine’s airways supported this effect. A twin-clutch transmission was also on board the S1 during training for Röhrl’s victorious storming of the peaks during the 1987 Pikes Peak mountain race in Colorado.

The S tronic is one of the most versatile solutions in Audi’s range of transmissions. In the spring of 2003, Audi introduced the technology in series production in the TT Coupe and Roadster, combined with the high-torque 3.2-liter V6 with 184 kW (250 hp). The ultra-compact twin-clutch transmission, designed for transverse installation with six gears, was the perfect complement to the powerful engine. TT pilots could use it in automatic mode or shift the gears by hand, either with the short shift selector lever or with rocker switches affixed behind the steering wheel.

In the past five years, the new technology in the TT and A3 has become firmly established – as dynamic high-tech alternatives to hand-shifting as well as being fully imbued with the positive attributes of a conventional geared automatic transmission. Due to its wide range of strengths, the S tronic is also available in the A3 with a TDI four-cylinder engine. By the end of 2007, Audi had produced 188,338 cars in both model lines with twin-clutch transmissions.

A wide-ranging program: the ideal solution for every need

Today, Audi has a wide-ranging portfolio of transmission technology options – five technologies with widely varying characteristics may now be selected to perfectly fulfill their specific range of applications. Aside from the sporty S tronic with six – and now seven – gears, Audi offers a classic manual transmission, an automatic R tronic, the comfortable tiptronic torque-converter transmission, and the versatile, continuously variable multitronic – at least two customized solutions are available for each model range. The common denominators among all of these transmissions are compact and light construction, high efficiency, precise functioning in extremely durable quality, and convenient and simple operation.

Manual shift transmissions are available in many of the model ranges, from the compact A3 to the A6, along with the TT, the Q7 and the R8; they are suitable for combination with front-wheel and quattro drives. In the A4 and A5 model lines, Audi has introduced a new generation of transmissions that are notable due to modified positioning of the differential and for their greatly reduced internal friction, which further improves efficiency. Most manual transmissions operate with six gears. In the A3 1.9 TDI e and A3 Sportback 1.9 TDI e, five-gear transmissions are used in which the upper gears feature a somewhat longer gear ratio – which helps sink consumption on average to an exemplary 4.5 liters of diesel per 100 km (52.27 mpg).

The sequential-shift R tronic with six gears is reserved exclusively for the R8; as befits the character of a supercar, the engineers have designed it to be especially dynamic. In the R tronic, hydraulic units manage activation of the gears and clutch, and the driver’s commands are transmitted electronically.

The tiptronic transmissions from Audi are found in all sedan model lines, from the A3 to the A8, as well as in the high-performance Q7 SUV, in combination with front-wheel or quattro drive. The great strength of this classic torque-converter transmission is in its highly convenient shifting. In order to improve this even further while also improving efficiency, in the latest configuration, engineers have modified the damping system in the torque converter. In addition, gear shifting is completed more swiftly.

The redesigned multitronic also features even greater efficiency and dynamics. The continuously variable transmission from Audi combines the advantages of manual gear shifting with the strengths of an automatic. As an especially comfortable driveline, the multitronic available in the A4, A5, A6 and A8 is paired with front-wheel drive. The new seven-gear S tronic developed by Audi, which will be introduced in series production in multiple models during the course of this year, is combined with quattro technology – Audi has designed it as a sporty and highly efficient high-tech transmission.

Volkswagen DSG – 7 Speed Mechatronic Control Unit

 

dsg_trans_mechatronics_7_speed_1Open communication

The mechatronic components represent the ‘brain’ of the 7 gear dual-clutch gearbox DSG. They can implement complex shift operations in a fraction of a second. They consist of a control device and control valve assembly together with individual sensors and actuators. If a shift is to be performed, the control device communicates the gearbox data to the vehicle electronics network. Conversely, information is transmitted via this interface from the vehicle and motor to the gearbox computer.

Closed system

The mechatronics module is an autonomous unit with its own oil circulation system. The advantages are obvious: 

  • The viscosity of the hydraulic fluid can be adjusted specifically to suit these operating conditions.
  • The high degree of purity of the hydraulic oil permits the use of so-called cartridge valves with extremely small clearances. The result: significantly lower leakage rates and therefore efficient operation of an electrically driven pump.
  • The mechatronic components can be installed independently of the gearbox and they can be exhaustively tested in advance.
  • The system is ‘hybrid-friendly’, because the dual-clutch can be engaged and the gears can be changed even when the internal combustion motor is not running.

dsg_trans_mechatronics_7_speed_2

Volkswagen DSG – 7 Speed Dual Clutch Gearbox

 

dsg_trans_7_speed_17 Speed DSG Gearbox

Maximum Torque: 250 Nm

Clutch: Dry

Transmission oil volume: 1.7 litres

Weight: 77 kg

Orientation: Transverse

More innovative, more intelligent – and more comfortable than ever

Here is Volkswagen’s new dual-clutch gearbox DSG – a real gearbox sensation. Why? Because it represents two world premieres at once: On the one hand it is the first 7 gear gearbox for front transverse mounting, and on the other hand it is the first dual-clutch gearbox with a ‘dry’ double clutch. What is the benefit for you? The comfort of conventional automatic transmission. The dynamic drive of a manual transmission.

Dried out: the innovative dual clutch

The essential component of the new 7 gear dual-clutch gearbox DSG is its ‘dry’ running clutch. It dispenses with the oil bath needed in conventional designs – a worldwide innovation in DSG technology. Together with other technical measures this makes the dual-clutch gearbox DSG significantly more efficient. The result: less fuel consumption and less emissions – more comfort, agility and driving satisfaction.

dsg_trans_7_speed_2Brand new: and already an award winner 

Thanks to the new 7 gear dual-clutch gearbox DSG this revolutionary gearbox technology can now be combined with smaller engines with a torque capacity up to 250 Newton metres. A development which recently found the acclaim of the ADAC*: In the category ‘Innovation and the Environment’, the German automobile association awarded the ‘Gelber Engel 2008’ exclusively to Volkswagen’s technology mix of TSI and 7 gear dual-clutch gearbox DSG.

 

Running dry – but still the engineer’s dream

About 400 parts. And only 70 kg. But what makes the design of the new 7 gear dual-clutch gearbox DSG so exceptional is its ‘dry’, hydraulically controlled dual-clutch. Apart from a range of different constructional advantages, this allows a considerable reduction in the amount of lubricant needed. For only the actual gearing and the bearings still require lubricating oil, and none is needed for cooling the clutch. The result: a significantly higher efficiency rating for the gearbox and therefore lower fuel consumption.

dsg_trans_7_speed_3

Perfect teamwork

The combination of mechatronics, intelligent electro-hydraulic gearbox control, a double-clutch, two drive shafts and three gear shafts means that the next highest transmission stage remains permanently ‘on hold’, simply waiting to be called on. And that takes place in the blink of an eye. Clutch 1 serves the odd numbered gears, whilst clutch 2 serves the even gears and the reverse gear. The effect is immediately apparent in the dynamic driving characteristics: There is no longer any loss of traction power during gear shifts.

A clear concept

Our aim: To achieve more agility and at the same time consume less fuel. Our solution: A seventh gear! Thanks to the innovative 7 gear configuration we have been able to design the first gear with a shorter range. That improves the start-up behaviour considerably. As the gearbox stages are close together and it is equipped with overdrive, the seventh gear with its large transmission ratio saves significantly more fuel – and therefore reduces the emission of CO2. One positive side effect is even audible – or rather inaudible – the vehicle runs even more quietly.

dsg_trans_7_speed_4Shared responsibilities   

 But how does the new 7 gear dual-clutch gearbox DSG actually work in practice? Here is an example: When the vehicle is travelling in sixth gear and accelerates further, the seventh gear is already engaged – but not yet active. When the ideal shift point has been reached the clutch for the sixth gear automatically opens. At the same time the other one closes and thereby activates the seventh gear. The result of this interplay between the two clutches: optimal driving comfort without any interruption of traction power.

 

Advantages – 7 gear dual-clutch gearbox DSG

Compared with conventional manual transmissions and converter transmissions the new 7 gear dual-clutch gearbox DSG is clearly at an advantage:

  • It allows for direct and completely smooth gear shift operations.
  • It is as driver-friendly as a full automatic transmission.
  • Lively handling characteristics and dynamic driving are guaranteed: through gear shifts without traction power interruption.
  • It responds positively and spontaneously, with extremely short reaction times.
  • And it is economical and helps to conserve resources: With the practically loss-free operation of the dual clutch it is even possible – depending on the driving behaviour – to reduce the fuel consumption to below that of manual transmissions.
  • Qualities which not only demonstrate the trailblazing nature of this transmission concept, but also something much more important: its day-to-day dependability. Never mind what driving conditions prevail, it ensures that the vehicle is driven correctly.

Volkswagen DSG – 6 Speed Dual Clutch Gearbox

dsg_trans_6_speed_16 Speed DSG Gearbox

Maximum torque: 350 Nm

Clutch: Wet

Transmission oil volume: 6.5 litres

Weight: 93 kg

Orientation: Transverse

DSG – the dual-clutch gearbox from Volkswagen

The innovative DSG dual-clutch gearbox from Volkswagen offers previously unattained shifting comfort that lifts what were once well-defined boundaries between automatic and manual transmissions. This is a 6-speed gearbox that combines the sporty character and low fuel consumption of a manual gearbox with the comfort and convenience of an automatic. Another highlight: gear changes are executed without any interruption of the driving power.

The DSG gearbox features two driving programs: normal mode and sport mode. In sport mode, the DSG shifts up and down later. Gearshifts can also take place in sequence manually using Tiptronic. They can be performed in particularly sporty style via Tiptronic switches on the multifunction steering wheel (available on selected models).

dsg_trans_6_speed_2The dual-clutch gearbox essentially consists of two independent gearbox units. With dual-clutch technology – two wet clutches in a common housing – both gearboxes are connected under load to the engine alternately depending on the current gear via two drive shafts. Clutch 1 serves the first gearbox unit with 1st, 3rd, 5th and reverse gear and clutch 2 the second gearbox unit with 2nd, 4th and 6th gear.
Each gearbox unit is assigned an output shaft that applies the torque to the driven wheels via the differential gear.

Thanks to the dual-clutch design the DSG is remarkably more efficient than the conventional automatic transmission that uses a hydraulic torque converter. This and its low weight, together with the intelligent transmission control, are vital prerequisites if vehicles with the dual-clutch gearbox are to achieve the same or even lower fuel consumption, depending on the style of driving, than a manual gearbox.

dsg_trans_6_speed_3The principle of overlapping gear changes in the DSG is as follows: when one gear is engaged, another gear is always preselected. If a gear change is approaching, one clutch opens within three to four hundredths of a second while the other closes. The mechatronics unit ensures that this takes place fast and accurately on a level that would not be possible manually. In this way, the change of gear is imperceptible to the driver and is achieved without any interruption of the driving power.

The decision as to which gear should be engaged next is taken by the control unit based on the position/operation of the accelerator, engine speed and vehicle speed. If the accelerator pedal is pressed and the vehicle accelerated, the next-highest gear will be preselected before the shift point is reached. If the accelerator is not operated, however, i.e. the vehicle is in overrun, the next-lowest gear will be preselected.

dsg_trans_6_speed_4The advantages in detail:

  • The Volkswagen DSG permits smooth gear-changing along with the additional comfort of an automatic gearbox.
  • The virtually loss-free dual clutch even cuts the fuel consumption of some models featuring DSG to below that of manual models depending on the style of driving.
  • The Tiptronic with manual, sequential gear selection offers sporty driving enjoyment due to direct gear-shifting.

 

dsg_trans_6_speed_5

Volkswagen DSG – 6 Speed Mechatronic Control Unit

dsg_trans_mechatronics_1

Clutches and gearbox units are operated hydraulically. This function is performed by the gearbox mechatronics, housed in the DSG. The term “mechatronics” is derived from a combination of mechanics and electronics. And this is exactly how the mechatronics module is structured: the electronic transmission control unit, various sensors and the hydraulic control unit form one compact unit.

The control unit uses information such as engine speed, road speed, accelerator position and driving mode to select the optimum gear and to determine the ideal shift point. The hydraulic control unit then implements the shift commands in a complex sequence of individual, precisely coordinated actions.

Conti Temic microelectronic GmbH, headquartered in Nuremberg, Germany – an international supplier of electronic chassis components for the automotive industry – employs Ultradur® B4300, a BASF polybutylene terephthalate (PBT), in the manufacture of the integrated control unit for its new double-clutch transmission. The transmission control unit is a sophisticated, compact mechatronic component installed directly on the gearbox, meaning that it is immersed in hot trans-mission oil. Two variants of this BASF plastic offer the requisite high-temperature and chemical resistance. This innovative automatic transmission – serially produced at VW for the first time in 2003 – has now found its way into the Golf, Touran, Passat, Jetta and the new Eos models.

Two clutches – eleven sensors – one control unit

The double-clutch transmission consists of two subgearboxes, each with its own clutch, that work together to shift the gears. The integrated electronic control unit that Temic developed for this transmission comprises 11 sensors and 11 actuators (e.g. valves) in one single component whose main function is to open one of the clutches and to close the other at the right moment. This results in smooth shifting without interruption of the tractive force. The electronic unit processes the sensor signals, measures the rpm’s, the speed and the load on the transmission, ascertains the positions of the mechanical components and electromagnetically operates the valves and slides of the hydraulic gear mechanism.

dsg_trans_mechatronics_2Such highly integrated mechatronic parts are only possible with the use of high-performance engineering plastics: Only a material that can be freely shaped is able to protect the electronic components while combining actuation and sensor technology in an extremely small space and in a single part. The wiring is simplified, the number of cables and plugs is drastically reduced, and interfaces are rendered unnecessary, thus yielding a component that is small, lightweight and reliable.

One plastic – two uses

Ultradur® B4300, a PBT made by BASF, fulfils a number of mechatronic functions in the control unit produced by Temic. The standard variant, B4300G6, containing 30 percent glassfibres, has all of the mechanical and chemical properties, for instance, dimensional stability, needed to withstand hot transmission oil. Semiconductor sensors secured in place with this plastic must not shift their position, even when exposed to high temperatures and oil. In contrast, type B4300K6, which is reinforced with glass beads, has to be highly isotropic, so that no oil can get into the structures. The Swoboda company located in Wiggensbach in the Allgäu region of Germany is in charge of the injection moulding of this plastic.

Volkswagen DSG Mechatronic Replacement

Mechatronic Replacement

02E325025ADZD6 (02E 325 025 AD ZD6) – Mechatronic Unit         USD$2200.00/AUD$2900.00

02E305051C (02E 305 051 C) – Transmission Filter USD$49.00/AUD$65.00

02E315141A (02E 315 141 A)- Gasket Pump  USD$50.80/AUD$66.00

G052182A2 (G05 218 2A2)- Oil, ATF DSG 1.0litre (x 6) USD$121.26/AUD$160.00

N91084501 (N91 084 501)- Seal, Trans Oil Filter USD$3.00/AUD$4.00

Total Price USD$2424.06/AUD$3200.00 + Labour (3-4 hours)

New DSG Transmission versus New Manual Transmission

DSG Transmission

(include Mechatronic Unit – deduct ~USD$1500/AUD$2000 if not required)

02E300042Q (02E 300 042 Q) – USD$6000/AUD$7800.00

02E300043C (02E 300 043 C) – USD$6000/AUD$7800.00

Manual 6 Speed Transmission

02Q300043K (02Q 300 043 K) – USD$4000/AUD$5300.00

02Q300040E (02Q 300 040 E) – USD$4000/AUD$5300.00

Reconditioned units for both DSG and MT gearboxes are available, these are indicated by an X on the end of the part number. For the DSG the gearboxes are ~USD$2000.00/AUD$2600.00 cheaper and for the MT ~USD$1500.00/AUD$2000.00 cheaper.