DSG gearbox - what is it, pros and cons

Direct Shift Gearbox (DSG)

Motorists have long been accustomed to two types of gearboxes - automatic and manual. At the beginning of the 2000s, another type of gearbox appeared on the roads, “preselective”, or, in other words, DSG (the English abbreviation for Direct Shift Gearbox). Such units are a merger of manual transmission and automatic transmission.

1. What is a DSG gearbox

The driver selects gears, and the electronics themselves control the clutch and give the command to change gears. A distinctive feature of such units is a double clutch and five shafts.

This solution made it possible to achieve the same acceleration time and maximum speed as with a conventional manual transmission. It would be correct to say that DSG is the next step in the development of manual transmissions. Such nodes are often called “robots”.

2. Design and technical details of DSG boxes

DSG boxes are divided into two types - DSG-6 and DSG-7, the first is a six-speed version, the second is a seven-speed version.

DSG-6 has high torque and operates on a “wet” principle. The mechanical parts are immersed in an oil bath, during which the oil circulates, thereby cooling the clutch components and discs.

Such gearboxes are installed on high-power vehicles:

• Volkswagen Golf, Volkswagen Eos$
• Skoda Octavia;
• Audi TT, AUDI Q3.

Examples of cars with seven-speed “robots”:

• Volkswagen Passat, Volkswagen Transporter;
• Skoda Fabia, some Octavia;
• Audi A3.

The operating principle of robotic boxes (“robots”) is as follows:

The common unit of such boxes is mechatronics, a unit that includes sensors, hydraulics, and electronic components. He monitors oil pressure readings, gear position, speed and other parameters and, based on this, decides whether to shift to a higher or lower gear.

3. Advantages and disadvantages of “robots”

A robotic gearbox has many pros and cons.

The advantages include:

• almost instantaneous gear shifting;
• Manufacturers claim fuel economy (debatable, except in comparison with a conventional automatic);
• There is no engine power take-off, as when driving a manual transmission;
• Manual control.

There are also many disadvantages:

• The cost of repair is high;
• Unreliable mechanical part even in new models;
• Expensive and complex procedure for changing oil in DSG-6 type boxes;
• Does not tolerate aggressive driving style well.
• cars with such a gearbox are more expensive than conventional hydromechanical “automatic” and “mechanical” ones.

As an example, let's take a budget foreign car Skoda Octavia with an engine capacity of 1.4 liters.

The price with a manual transmission is 1,034 thousand rubles; for the box with DSG they want 1,074 thousand rubles, however, the manufacturer claims fuel economy of 0.1 liters for every hundred kilometers. At a dealership, a “robot” will cost 40-60 thousand more than a conventional manual, 10-20 thousand more than an “automatic”.

4. Opinions and reviews

Reviews from owners of such cars are extremely contradictory. On one side of the barricades are car enthusiasts happy with the choice, on the other - disappointed and trying to dissuade them from such a controversial purchase. The State Duma even recorded an attempt to completely ban DSG 7 gearboxes in Russia.

The argument was concern for citizens; deputies expressed the opinion that such a box was not safe for drivers. Fortunately, the case did not even reach the initial hearing.

DSG supporters cite arguments such as “working on the mistakes” of DSG manufacturers (a dubious advantage), quick gear shifts that do not depend on driving skill, low fuel economy, stable operation at low temperatures, and positive dynamics.

Detractors are countered by the fact that they incorrectly read the instructions for the car. Indeed, manufacturers recommend, in contrast to hydromechanics, to turn on neutral in traffic jams or at traffic lights. However, these are just tips.

There are many more opponents and the arguments are stronger. The software is unreliable, difficult to maintain, often cannot be repaired at all, the entire unit changes, and this affects the cost.

“Garage” repairs are excluded; even if a regular automatic transmission can be repaired in a car repair shop with competent employees and a set of tools, then no one except official dealers will take on the DSG.

Women complain about the rollback in traffic jams, men complain about the impossibility of a quick start from a traffic light (a tribute to reliability, when the first gear is engaged, the box “thinks”).

At second speed, vibrations are felt and extraneous noises are heard in the box. A common occurrence is a breakdown due to the firmware, for example, the “brains” stop recognizing even-numbered gears. There is an opinion that such systems are poorly compatible with gasoline and behave slightly better with diesel fuel.

In hot weather, clutch discs overheat on “dry” gearboxes and cannot be repaired, only replaced. It’s not for nothing that people say this: DSG – Two Clutches per Year.

There are much more bad reviews than positive ones. The negative nature of the responses is clearly visible.

On the other hand, if everything was really so bad with them, such boxes would not have become so widespread, but judging by the models on which they are installed, there are still a lot of them.

Perhaps automakers will not admit to their mistakes; again, re-equipping conveyors is a costly business, but making people believe in quality and reliability is the job of marketers and PR departments.

5. Conclusions

The decision to choose a robotic gearbox is made solely by the future owner. If you are not a fan of aggressive driving, you are ready to spend money at an official dealer, you don’t like the “sluggishness” of automatic transmissions, but you also don’t want to lose comfort because of the clutch pedal - DSG is quite suitable.

Again, in pursuit of the client, such boxes usually come with an increased warranty. For example, Volkswagen claims 150 thousand kilometers without repairs. Those who like to leave a traffic light abruptly should look towards the “mechanics”.

If small jolts and fuel consumption are not critical, buy a car with a conventional automatic transmission.

In Russian conditions, DSG does not take root very well. Perhaps, corporate engineers will soon find a solution to many problems, as has happened more than once, but for now “robots” are the most common lottery. Whether to play it or not is your choice. But if the question arose only about DSG, then choosing a six-speed model is preferable in terms of reliability and dynamics.

Source: http://ProCrossover.ru/avtolyubitelyu/akpp/korobka-pryamogo-pereklyucheniya-pereda.html

What is a DSG gearbox?

This type of transmission belongs to the so-called preselective robotic gearboxes, the design feature of which is the use of two separate transmission units with shafts for even and odd gears, and each shaft is controlled by its own clutch.

DSG robotic gearbox diagram

There are two types of such clutches - wet (using an oil bath) and dry (without using an oil bath), the second is considered more progressive.

An important role in the design of such a transmission is played by the Mechatronik clutch control unit, which, using data on the crankshaft speed, vehicle speed, gas pedal position and gearbox operating mode, determines the optimal moment to engage an upshift or downshift. He then sends a command to the hydraulics, which changes gears. The main advantage of such a transmission is the sequential shifting of gears without interruption of torque due to the fact that their shifting occurs in advance: while, for example, the first gear is engaged, the second clutch is activated, and when the optimal torque for moving to a higher level is reached, the first clutch opens and then the second clutch closes. DSG gearboxes (“Direct Shift Gearbox”) are installed on Volkswagen cars; on models of other brands, such transmissions are also used, but have different names - PDK, DCT, SST, S-Tronic and so on.

Let's return to the DSG. Currently, there are two types of this transmission - a six-speed with a “wet” clutch and a seven-speed with a “dry” clutch. Both gearboxes have their pros and cons. Let's start with the advantages.

In addition to the smooth and fast (up to 8 ms) gear shifting mentioned above, the advantage of this box is its optimal combination with engines whose torque is less than 250 Nm.

Another advantage is efficiency, which is achieved due to the fact that when changing gears there is no interruption in the flow of engine power, therefore, fuel is not wasted to restore engine power.

It is possible to change gears in both “automatic” and “manual” modes (the latter involves controlling the transmission as in a conventional “mechanics”).

Now about the disadvantages of the DSG box. First of all, this is the high cost of a car with such a transmission. The high price also affects the high cost of maintenance (changing transmission oil) and repairing the double clutch gearbox.

In Russia, as practice shows, it is almost impossible to repair such boxes, so dealers often resort to complete replacement of the unit. Another disadvantage of this box (typical for a seven-speed gearbox, although previously noted for a six-speed DSG) is jerking when moving in first gear.

Also, this transmission is characterized by rolling back when starting a car uphill.

DSG

Source: https://avtoexperts.ru/article/chto-takoe-korobka-peredach-dsg/

All about DSG: advantages and features

What is DSG? In German, the abbreviation DSG stands for “direct gearbox” (Direkt Schalt Getriebe). It is often called “preselective,” that is, able to hold gears ready for the next shift.

The idea of ​​​​creating such a checkpoint belongs to the French inventor Adolphe Kegresse. In the 30s of the last century, an automotive engineer collaborated with Citroen. He proposed installing a unit with two clutches and hydromechanical control on the front-wheel drive Citroen Traction Avant. The new transmission has not received widespread use due to its complex design.

Volkswagen Favorite Hoff technical consultant Maxim Ponomarenko spoke about the advantages and features of the box.

How DSG works

The fundamental difference between a preselective automatic transmission and others is in two clutches that quickly change gears.

In a manual or robotic gearbox, to change gears, the clutch disc is disconnected from the flywheel, the driver or robotic computer selects the desired “speed”, and after that the disc snaps into place. During this time, torque is not transmitted to the box and the car loses dynamics.

The DSG system allows you to get rid of power failures. The box is based on the operation of two shafts located coaxially: the first is hollow, and the second is inside it.

The engine is connected to each of them through its own, separate multi-plate clutch - also external and internal.

The gears of the even gears (2nd, 4th, 6th) are fixed on the primary, that is, the outer shaft, and the gears of the odd gears (1st, 3rd, 5th and reverse gear) are fixed on the inner shaft.

When the car starts, the odd-numbered disk is pressed against the rotating flywheel, while the even-numbered “speed” disk is open. During acceleration, the computer unit of the box gives the command to prepare the second gear, so that at the moment it is turned on, it disconnects the odd-numbered row disk and immediately puts the even-numbered disk into operation. Tuned shift control ensures no loss of torque.

The DSG 6 robotic gearbox entered the Volkswagen assembly line in 2003. The double clutch on it operated in an oil bath, receiving the name “wet”. The oil in such a box takes away some of the power, increasing fuel consumption. In 2008, the German automaker introduced a seven-speed DSG 7 with a dry clutch.

DSG benefits

• The DSG box, due to the optimal modes of switching on the desired “speeds”, allows you to reduce fuel consumption. Cars with it consume about 10% less fuel than cars with a conventional gearbox.
• A distinctive feature of all such transmissions is dynamic acceleration. To shift up a gear, the box needs only 8 ms; it does not have the effect of rubber traction as on hydromechanical automatic transmissions.
• You can drive the DSG in manual mode, that is, change gears manually.
• This automatic transmission is 20% lighter than a similar hydromechanical transmission.

Disadvantages of DSG

• The cost of automatic transmission affects the price of the car, significantly increasing it.
• Expensive oil changes (on a six-speed gearbox) every 60 thousand kilometers. The total volume is 6.5 liters.

The preselective box is installed on different models and brands united under the name of the Volkswagen automaker: Audi TT (A1, A3, A4, S4, A5, A7, A6, Q5, R8), SEAT Ibiza (León, Altea), Škoda Octavia (Superb, Yeti), Volkswagen Polo (Golf, Jetta, Touran, New Beetle, Passat, Passat CC, Sharan, Scirocco, Caddy).

Extended warranty for DSG

Among many car owners, the dubious glory of a dual-clutch transmission has gained a foothold. The name DSG itself has become a symbol of an unreliable design with costly repairs. In fact, Volkswagen has long ago taken control of the current situation. An important step towards quality control is a large-scale service campaign.

The concern provides an extended warranty for seven-speed gearboxes manufactured before January 1, 2014. According to representatives of the automaker, the indicated period corresponds to the appearance on the assembly line of a modernized transmission without the typical problems of the previous generation.

Special service conditions are limited to 150 thousand mileage or 5 years of age of the mechanism. The service promotion includes replacing synthetic oil with mineral oil, which is less aggressive towards electronic components. At the same time, the firmware of the automatic transmission control unit is updated.

Detected faults are eliminated free of charge - this applies to repairs, replacement of individual elements or the entire transmission.

In any case, you should not be afraid of the DSG abbreviation: with the proper level of service, it will not let you down, and in terms of the number of advantages, the “smart robot” outperforms the classic automatic transmission. And the DSG gearbox will require less money for repairs compared to a conventional automatic transmission.

What malfunctions are typical for DSG?

The most common problem is the jolts that accompany the movement when changing gears. The clutch discs close too quickly and the car jerks. The second known drawback is vibration at start-up, clanging, grinding and other extraneous noises during gear changes.

The main reason for the incorrect operation of the seven-speed transmission is its “dry” clutch. It wears out quickly due to harsh operating conditions in dense city traffic, with congestion at low speeds. Therefore, the question “how to operate DSG?” There is one obvious answer - avoid the gas-brake mode, because the robot’s main enemy is a traffic jam.

Other problems include wear on shaft bushings, clutch release forks, broken solenoid contacts, dirt on sensors and oil in antifreeze.

How to determine a DSG malfunction when buying a used car?

• Some gears do not engage - the box “skips” them.
• Gear shifting is accompanied by shocks - the box “kicks”.
• There is a hum when driving.
• The car vibrates when starting.
• An inspection on the lift shows that oil is leaking from the box.

If you suspect that the box is not working correctly, you should order an additional check, or postpone this option.

Trust your choice to trusted used car sites. FAVORIT MOTORS is a team of experienced specialists, whose results are confirmed by first places in sales ratings.

We sell prepared cars that have undergone detailed diagnostics. They have no hidden defects and a “transparent” legal history.

You are purchasing a car that exactly meets your expectations, exactly suited to your needs.

Source: https://favorit-motors.ru/articles/rekomendatsii/vse-o-dsg-dostoinstva-i-osobennosti/

DSG gearbox - operating principle, pros and cons

For a long time, traditional manual transmissions were considered the most reliable units, capable of serving for a long time with proper vehicle operation without any intervention or troublesome maintenance. However, the owner of a manual car is doomed not only to constant manipulation of the gearshift lever, but also to filigree work with the clutch and gas pedals.

If you accidentally release the clutch pedal in a careless manner, the car will jerk mercilessly. But, if over time the use of a manual transmission can be brought to automaticity, practically without paying attention to the gear shifting process itself, then problems caused by frequent stopping and starting in traffic jams cannot be avoided when owning a car with a manual transmission.

As informal surveys of drivers who have become car owners in recent years show, it was daily city traffic jams that became the reason for choosing a car equipped with an automatic transmission.

It should be noted that, with other equal equipment of a car of one model or another, the version with an automatic transmission will cost the buyer several tens of thousands of rubles more than the version with a manual transmission.

Hydromechanical automatic transmissions make the driver's life much easier, because they independently switch to the desired gear, without requiring constant squeezing of the clutch. At the same time, the feeling of pulsation of engine thrust is smoothed out by the torque converter. However, even modern, very reliable hydromechanical gearboxes have their drawbacks.

The main ones are considered to be a decrease in engine power due to hydraulic losses, as well as an increase in fuel consumption. The emerging robotic gearboxes, which have a system of electric drives for gear shifting and clutch, have not solved the problem either.

Even the luminaries of the BMW company have still not been able to bring the operating algorithms of robotic gearboxes to perfection, as well as ensure a high level of reliability of such units.

As a solution to the problems of traditional “mechanics” and to eliminate the shortcomings of standard hydromechanical automatic transmissions, VAG specialists have developed an innovative 6-speed DSG gearbox (Direktschaltgetriebe or Direct Shift Gearbox). This unit was first installed in 2003 on the Volkswagen Golf R 32 model.

The idea of ​​DSG itself turned out to be quite simple. In order for the gear shifting process to be optimal, not one, but two gearboxes must be installed on the car - one for even gears, and the other for odd gears, and each of them must have its own clutch unit.

While acceleration is being carried out using an even gear, the next one, odd, is also turned on, waiting for the current traction force to be transferred to it. Based on this principle, the DSG is usually called a preselective transmission .

As soon as it is time to change gear, the even-numbered clutch opens, and the odd-numbered clutch closes synchronously.

Thus, the process of transferring traction force from one gearbox to another turns out to be seamless, which not only ensures the conservation of power, but also eliminates jerks and dives characteristic of conventional manual gearboxes. Of course, the DSG boxes installed on many VAG models are a single unit, but the general principle of its operation is exactly as described above.

It would seem that the “recipe” for the ideal gearbox has been found, but several circumstances prevented the mass use of DSG.

The fact is that DSG, installed on cars with relatively “weak” engines, was significantly inferior in fuel efficiency to similar cars equipped with conventional “mechanics”.

The pump serving the powerful DSG hydraulic drives constantly took a fair amount of engine power. Another source of horsepower loss was “wet” clutches, whose efficiency indicator is, by definition, inferior to that of a “dry” clutch.

It turned out that six-speed DSGs could only be installed on models with fairly powerful engines. That is why Volkswagen, Skoda and Seat models are equipped with a similar gearbox, under the hood of which the most powerful engines are installed.

Literally immediately with the start of mass production of cars with DSG 6 gearboxes, German engineers introduced a new modification of the DSG gearbox, designed specifically for car models with relatively low engine power. We are talking about a 7-speed DSG 7 .

This gearbox, in addition to seven gears, has a “dry” clutch system instead of the previously used set of “wet” clutches. Another innovation was the presence of an electrically driven oil pump. It is used only if the pressure level drops below a critical level, without constantly taking away engine power.

DSG 7 is a more economical unit than DSG 6, in addition, the seven-speed gearbox is much lighter than its six-speed counterpart. However, the DSG 7 is capable of handling around 250Nm of torque, which is 100Nm lower than the six-speed wet clutch.

That is why the area of ​​DSG 7 is tandems with not the most powerful engines, for example the 140-horsepower 1.4 TSI engine installed under the hood of the Skoda Octavia or the 85-horsepower 1.4-liter engine installed in the Volkswagen Polo.

In addition to the dual clutch system and two rows of gears, the DSG design is characterized by the presence of a final drive, differential and control system, which are located in the gearbox housing.

The dual clutch consists of a drive plate connected via an input hub to the flywheel, as well as a pair of friction multi-plate clutches connected to both rows of gears by the main hub. The wet clutch installed on the DSG 6 is always in an oil bath.

The seven-speed unit has a dry clutch unit, requiring a significantly smaller volume of oil to be filled. In addition, on the DSG 7 the hydraulic drive of the oil pump is replaced by an economical electric pump.

The first row operates the odd gears and reverse, the second row operates the even gears. Both rows are shafts with gear blocks located on them. The input shaft gears are rigidly connected to the shaft. The secondary shaft gears rotate freely.

At the same time, the gears of both shafts are constantly engaged with each other. The synchronizers that engage a specific gear are located between the gears on the output shaft.

The control system, which controls gear shifting and clutch control, includes an electronic unit, input sensors and an electro-hydraulic unit.

The electro-hydraulic and electronic units, as well as the input sensors, are integrated into a common module called Mechatronic . It is located in the box housing itself and is the most problematic unit of DSG boxes.

In general, speaking about the shortcomings of the presented gearbox, it is worth noting that with an active driving style, the control units included in the Mechatronic design quickly wear out, resulting in the need for expensive repairs.

In addition, in conditions of prolonged standing in traffic jams, in order to avoid premature wear of gearbox parts, the manufacturer indicates that it is mandatory to shift the gear lever to the neutral position.

Another, not the most pleasant feature of the operation of DSG gearboxes is possible noise and knocking when switching from second to third gear. It is noteworthy that the manufacturer officially explains such a clanging sound in the box as a design feature of its operation that does not affect the durability and reliability of the entire unit.

It should be noted that not so long ago, problems with the failure of DSG gearboxes, especially its seven-speed version, began to become so widespread that the VAG concern was forced to approve an extended warranty program for this expensive automobile unit, increasing the warranty period to 5 years or 150 thousand kilometers. The situation was most acute with the Skoda Octavia and Volkswagen Golf models, which were equipped with DSG 7.

Today, there are no more problems with DSG gearboxes than with any other gearbox. At the same time, the presented transmission has a number of undeniable advantages . This transmission reduces the time it takes for the car to accelerate to the desired speed, making shifts almost imperceptible.

When driving the car, it feels like the car is constantly moving in one gear, accelerating and decelerating when required. The transmission selector is not only similar in use to conventional automatic transmissions, but also provides the option of manual shifting.

To do this, you need to move the lever up or down.

Source: http://www.octavia-avto.ru/info/korobka-peredach-dsg

Disadvantages of the DSG-7 gearbox

Manufacturers of modern cars are constantly improving their vehicles. New technologies appear, cars become powerful. Improvements have also been made to gearboxes.

Like its predecessors, the checkpoint has advantages and disadvantages. We will help you explain the causes of problems in the DSG 7 box. You can see additional information in the video located at the end.

 We'll tell you what the disadvantages of the DSG-7 gearbox are.

The DSG 7 gearbox is a universal seven-speed automated control with front-wheel drive. For the first time, such a box began to be used in 2006. It began to be produced by the famous Volkswagen company. The main advantage of the Volkswagen DSG 7 is the presence of two clutches. Due to them, the car quickly switches gears and moves smoothly on the highway.

The DSG 7 gearbox is mechanical, but with elements of an automatic transmission. Speeds in this version are switched automatically. Today this system is present in many vehicles from Skoda, Audi, Volkswagen, etc.

What's included in an automated transmission? The mechanism consists of:

• Mechatronic (control system);
• multi-plate clutch;
• primary and secondary pulley;
• main body.

The operation of the box is directly carried out by the Mechatronic system. This device consists of:

• Holla sensor;
• electrohydraulic control system;
• a large number of wires;
• mechanism for performing driver tasks.

DSG 7 works according to certain principles. To switch the car to high or low speed, the on-board computer automatically disconnects the clutch flywheel disc. The required speed is turned on, the disk is automatically connected to the system. The main feature of this box is that it minimizes the time spent changing gears.

Now let’s take a closer look at why the mechanism needs two clutches? The first clutch of the DSG 7 is responsible for switching odd speeds, and the second is responsible for switching even speeds. When the car starts to move, the first clutch disc is connected to the flywheel, and the second one is disconnected at this time. When the speed is gained, the laptop sends a signal to the system and the clutches change.

Compared to DSG 6, the improved version features a dry clutch, DSG 7, which is installed on cars with a less powerful engine. DSG clutch replacement is carried out by qualified specialists.

There are many myths on the Internet about robotic gearboxes. Some car enthusiasts read about the advantages, while others read about the disadvantages. But they are not able to accurately formulate advantages and disadvantages.

We will show you to know the most famous advantages and disadvantages of this model.

Pros of the device

Based on many years of experience, the conclusion is that the box has many disadvantages and few advantages. Although there are few advantages, they exist. Let's look at the most relevant ones.

Firstly, fast gear shifting. This is the main positive side of the portable mechanism.

Secondly, thanks to the mechanism, the driver can choose to control the speeds independently or trust the system.

A big plus is the low absorption of machine fluid. Unlike DSG 6, the new version consumes 5 times less engine oil. In addition, fuel consumption is 15% less.

Disadvantages of the device

The downside is that when you buy a car with such a system, you never know how long it will last. Based on all the information, we have selected several problems that 85% of motorists face:

• When changing speed, the car may produce slight vibrations or rocking (This is due to the presence of a dry clutch);
• Cars with built-in DSG 7 are prohibited from towing. When towing, you can severely damage the clutch and break the belts. Replacing a DSG clutch will cost a pretty penny. This means if the car stalls, you need to call a tow truck. If you try to start it yourself, there is a chance of severely damaging the car;
• the mechanism is not installed on vehicles with a longitudinal motor;
• extraneous sounds under the hood while driving. Typically, motorists hear such sounds while driving over a speed bump;
• due to the complex design of the mechatronics dsg 7, few craftsmen take on the job. This is due to the fact that our specialists have little experience working with such a system. Automatic transmission repair requires a lot of time and good equipment. Therefore, not every master will want to take on the job at his own risk;
• Troubleshooting costs a lot of money;
• under heavy loads the mechanism overheats. This is a big disadvantage for motorists who are often stuck in traffic jams or drive long distances. When working for a long time, the robot overheats and begins to function slower;
• The clutch often breaks. A common problem if the car is driven off-road or on bad roads. Manufacturers of Volkswagen DSG 7 warn their users that the mechanism is not designed for constant off-road driving. Therefore, the device is best used in urban areas;
• dry clutch. Because of this, the machine wears out quickly. Due to incorrect mechatronics algorithms DSG 7, the machine does not function properly. Shaft bushings, pads, and forks wear out quickly. The car has to be repaired frequently, and automatic transmission repairs cost a lot of money;
• dirt sticks to the sensor. The sensors are not working properly. The laptop computer does not see all the problems. Because of this, there may be frequent machine breakdowns. When the sensor is dirty, the device may not indicate that the machine has overheated, as a result of which an important part may burn out. The DSG 7 may require a deep repair, which costs a lot of money. In addition, not every auto repair shop will want to repair the DSG 7 device.
• mixing antifreeze with oil. The problem occurs very rarely. Because of this problem, you will have to completely replace the DSG 7. When coolant gets into the oil, the device fails and becomes faulty. The motorist may not immediately notice this problem and continue to operate the car. This will lead to very bad consequences;
• Holla sensors. We have already mentioned them above. According to drivers, the device repeatedly turned off traction if the Hall sensor did not work. The mechanism monitors the location of the gear shift lever. If it malfunctions, incorrect information appears on the display. The equipment fails and requires replacement dsg 7;
• double drum clutch and flywheel. With the advent of this mechanism, the bearings began to wear out heavily. The clutch constantly breaks for this reason. If metal dust gets into the gearbox, the device fails. This harms the system. DSG 7 needs constant repair.

From the pros and cons we have listed, it is noticeable that there are many more disadvantages than advantages. This is primarily due to the complex design mechanism. There are flaws in it that disable the machine. The developers are trying to fix all the problems. Perhaps the device will soon become better. In the meantime, the device functions as before.

Source: https://skodakodiaq.club/nedostatki-korobki-peredach-dsg-7/

Review of direct shift gearbox DSG 6 and 7 steps

Home page » Transmission » Review of direct shift gearbox DSG 6 and 7 steps

The DSG automatic transmission is a unit equipped with a double clutch. Such gearboxes are installed on cars produced in 2013, 2014, 2015, 2016 by VAG.

The driver of the car selects the speed, and the transmission control module automatically controls the clutch and transmits the appropriate commands to shift gears. The main feature of robotic gearboxes is the presence of two clutches in the design, as well as five shafts.

Thanks to this, car manufacturers were able to achieve maximum speed with a short acceleration time, as with a conventional “mechanics”.

The design of the DSG gearbox includes the following elements:

• two rows of gears;
• double clutch;
• crankcase device;
• control module for receiving, processing and transmitting signals;
• differential;
• smooth transmission.

DSG gearbox device

Kinds

There are two types of robotic transmissions:

1. Six-speed. These cars use a double wet clutch. It always works in oil, which is used to lubricate the rubbing elements and cool the discs. This helps to increase the service life of the transmission unit. This gearbox is not the latest model of Volkswagen robotic gearboxes, however, it is considered one of the most powerful. The torque varies around 350 Nm.
2. Seven-speed. Such gearboxes use a “dry” clutch, which is why the unit requires three times less lubricant. Unlike six-speed gearboxes, which used hydraulically driven oil pumps, seven-speed gearboxes are equipped with electrical devices. This reduces energy consumption and increases the fuel efficiency of the power unit. But clutch life is shorter. Seven-speed transmissions began to be installed on cars three years after the release of DSG 6 and they are intended for more budget car models. The total weight of the box varies around 70 kg. The gearbox torque is no more than 250 nm. The main feature of this type of transmission is that it is equipped with two friction clutches that do not operate in an oil bath. Thanks to this, engineers were able to achieve the highest efficiency of the unit.

Principle of operation

The main catalyst that ensures the transmission of torque to both rows of gears is the double clutch of the automatic transmission. Thanks to it, the master disk starts.

This element is connected to the friction clutches, as well as the flywheel, through a special hub with another built-in flywheel. Thanks to the hub, both rows of gears are combined.

The first one works only with odd speeds and reverse gear, and the second one works exclusively with even ones. Each row of the transmission unit functions in conjunction, consisting of two shafts with gears.

The main component of any unit is the control module, consisting of:

• controllers designed to collect information from various vehicle systems;
• electronic component used to control the unit using a computer utility;
• hydraulic device;
• mechanisms and components designed to execute commands issued by the control module.

The Bereg channel published a video showing a test drive of a car with a robotic gearbox.

The central processor is installed directly in the gearbox housing, that is, in the transmission housing. The hydraulic device, as well as electronic components, are located in one unit - mechatronics. Controllers, to which impulses are transmitted from other machine systems, are installed in the same block.

Input regulators are used to read information about how rotation occurs at the output and input of the transmission unit. Thanks to them, they diagnose the temperature of the lubricant, the pressure in the system, as well as the correct location of the gearbox forks.

The control module receives data from the controllers, as a result of which the system launches one of the cycles stored in the memory of the central processor program.

A hydraulic or electrical device is used to adjust the transmission circuit.

The main components of this system:

• control and solenoid valves, the former are used to control pressure levels;
• distribution spools;
• multiplexer.

When the driver moves the gear lever, the switchgears begin to operate. The speed switching procedure is carried out as a result of the action of solenoid valves. The process of adjusting friction clutches is carried out under the influence of pressure valves. These components are considered executing.

The multiplexer is installed in the gearbox to control the hydraulic cylinders. There are eight of them in total, but during operation of the unit only four valves operate simultaneously. When the driver switches the gearshift lever positions, the multiplexer operates in different modes, resulting in different cylinders functioning.

But there are always four of them.

User Yaroslav Efremov in his video talked about the main malfunctions characteristic of robotic boxes.

Basic faults

In the operation of even the most reliable automatic transmission, breakdowns and errors can occur, which lead to the repair of units.

Below is a list of problems that, according to reviews from owners of cars with DSG, occur most often:

1. Failure of the clutch due to rapid wear. The main symptom of this problem is the periodic loss of reverse speed, and when the driver engages the gears of an even row, the car begins to move with jerks and jerks. Since the box is controlled by a central processor, the unit can automatically go into emergency mode. In this case, one of the speed rows will not be turned on. An error will remain in the memory of the central processor, which will allow the fault to be identified using computer diagnostics. To correct the breakdown, you will need to replace the friction clutch assembly or individual disks of this assembly. Usually, changing individual elements is relevant if the vehicle’s mileage is no more than 150 thousand km. When performing repair work, adjustment is necessary using a diagnostic stand. Also, the clutch of the box must be adapted to the car while driving.
2. Failure of mechatronics solenoids due to wear. We are talking about elements designed to regulate pressure. Failure of the solenoids causes jerking when changing gears. The unit can continue to operate in this mode, since the central processor does not see this problem and does not leave the error in its memory. To get rid of the malfunction, you will need to replace the solenoids or install a new mechatronics on the gearbox.
3. The mechatronics control module began to work intermittently. Such problems clearly manifest themselves during a cold start of the car engine. The transmission unit begins to operate in emergency mode, but after restarting the internal combustion engine continues to function normally. The main feature of this problem is that the transmission can go into limp mode unpredictably, for no apparent reason, when the car is moving. The control module writes the corresponding errors to memory. To solve the problem, it is necessary to change the mechatronics or central processor. In some cases, the control module must be repaired.
4. Failure of bearing elements, the mechanical component of the unit on the input shaft as a result of wear. The system differential may also break. The main “symptom” of this problem is the appearance of noise from the gearbox while driving. When the driver presses the gas pedal and the crankshaft speed increases, the sounds become louder. If the differential has failed, the noise will also appear when entering a turn. Sometimes it appears during sudden acceleration or braking of the car. Such problems can have serious consequences for the transmission unit. If they are not corrected in time, other components of the gearbox may fail. As a result of a breakdown, wear products in the form of metal dust will clog the mechatronics. The device may not work correctly and may break down over time. In this case, clutch wear will be faster. As a result, the malfunction will lead to the need for a major overhaul of the gearbox. Please note that it is impossible to find new bearings, differentials and shafts on sale; DSG manufacturers do not produce such spare parts. Therefore, if replacement is necessary, you will have to look for parts on the secondary market.
5. Another problem is the failure of the dual-mass flywheel due to wear. The first sign of a problem is the appearance of noise and clanging when the engine is idling. Sounds also appear when the power unit starts and stops. To get rid of the problem, the flywheel is changed.

1. Failed clutches of the robotic gearbox2. Worn transmission bearing parts

Troubleshooting

In Audi, Seat and other VAG cars, almost all faults are mechanical in nature. If the moving components and units of the unit wear out, they must be replaced.

Please note that elements wear out much faster when the driver sharply increases speed and brakes just as sharply, or often sits idle in traffic jams. Repair work related to the central processor is best left to specialists.

If you make mistakes when installing the control module or flash it incorrectly, this will lead to serious problems in the operation of the unit.

Oil change intervals and cost

The lubricant change interval depends on the manufacturer, as well as the make of the car. In DSG 7 0AM and 0CW gearboxes there is no need to change the oil, since it is filled for the entire service life of the machine. In all other transmission units, lubricant is filled in at 60 thousand km.

It is necessary to change the oil in the following cases:

1. If problems arise in the operation of the transmission unit. The box began to kick and push when changing gears, but all its component components and mechanisms were intact. Such problems indicate the use of low-quality transmission fluid.
2. If the oil turns black and deposits appear in it in the form of metal shavings and other wear products. It is necessary to identify the malfunction and remove it, and then start flushing the unit and replacing the lubricant. Over time, wear products will clog the channels of the system, which will lead to its inoperability.

In addition to the lubricant, it is recommended to change the filter when replacing. Depending on the car model, the box can hold different volumes of oil - from 2.7 to 7.6 liters. The cost of one liter of original liquid averages about 1,100 rubles.

On the Diocar channel, he published a video showing the process of replacing the transmission fluid in the unit.

Operating rules

To prevent malfunctions and ensure the reliability of the transmission, you need to know how to use it:

1. When you switch the main gearbox modes with the lever, the brake pedal should be pressed all the way. The design of the robotic transmission is such that if the driver presses the brake weakly, the clutch discs will not be able to open completely, which leads to their rapid wear.
2. Try to use neutral speed as little as possible. If you are stuck in a traffic jam or plan to stop for no longer than one minute, then it is better to coast. In this case, on the box itself, the selector should be moved to position S. This will reduce the likelihood of wear on the clutch unit and prevent damage to important structural components of the unit.
3. Vehicles equipped with robotic gearboxes cannot be used for towing. The transmission is designed for a certain vehicle weight, so it is not allowed to tow other vehicles or use a trailer on such vehicles. An exception may be SUVs. Their mass is quite large, so the load on the box will not be so critical.
4. Never skid your car; we are talking about a sudden start of movement with wheels slipping.
5. If you move the gear selector to the parking position, you do not need to release the brake pedal. The handbrake should be raised to prevent the limiter from failing if the car starts to roll back.
6. All positions of the gearbox selector must be engaged smoothly, observing a second delay. Please note that electronics need a certain time to adjust to a particular mode.

These rules are similar to controlling a traditional machine, but in the case of “robots” there are some peculiarities.

Such transmissions, unlike classic automatic transmissions, can transfer the car from position D to reverse driving mode without a pause at neutral speed. On cars with an automatic transmission, you can drive with slippage.

This is harmful for the transmission unit as a whole, but not as critical as for robotic gearboxes.

If you get into a snowdrift or are stuck in the mud and you cannot get out of the obstacle under your own power, then when pulling the car out of the snowdrift, the gearbox selector should be switched to neutral gear.

When towing a vehicle, remember that the speed of movement should be low. There is also a certain distance that a vehicle can be towed.

This data is usually indicated on the front pillar of the car.

User JoRick Revazov published the video. in which he talked about the mistakes of car owners of cars with DSG.

Pros and cons of "robots"

Let's consider the advantages of robotic transmissions:

1. In such gearboxes, gears change almost instantly. Thanks to this, the driver does not lose precious seconds when overtaking or performing other maneuvers on the highway.
2. All manufacturers of cars equipped with robotic gearboxes claim fuel savings. This is a debatable advantage. Perhaps such cars actually consume less fuel, but only compared to automatic transmissions.
3. DSG boxes do not take power from the power unit like manual transmissions.
4. Manual control of the unit will allow the driver to independently choose the mode in which it is better to move.

The main disadvantages of DSG:

1. High cost of repairs. If a part or mechanism on the “robot” fails, you will have to pay a lot of money for repairs. It may be difficult to find spare parts.
2. The mechanical component in such units is not reliable. Even if we are talking about new cars.
3. The process of changing transmission fluid is complex. Changing lubricant in a garage is problematic due to the design features of the unit. If you turn to a service station for help, you will have to pay a hefty sum for a replacement.
4. Robotic transmissions have a negative attitude towards an aggressive style of movement. The components and elements of such gearboxes wear out faster during sudden starts and braking.
5. The cost of vehicles with a robotic transmission is higher than those with automatic or manual transmission.

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conclusions

Let's look at what is more reliable in general - a robotic gearbox, an automatic transmission or a manual transmission. As practice shows, such transmissions are not reliable compared to other types of gearboxes.

Despite all the advantages, “robots” are very sensitive to improper operation. If you make mistakes during use, this will lead to rapid failure of the gearbox.

If you follow all operating rules, there will be no problems using the unit.

Video “How to properly change the oil in a DSG gearbox?”

The oasex channel published a video in which the procedure for replacing lubricant in a robotic transmission is discussed in detail using the example of a Skoda Octavia car.

Do you have any questions? Specialists and readers of the AUTODVIG website will help you ask a question

Source: https://autodvig.com/kpp/korobka-dsg-6-20417/