(Audi DL382 transmission)
Probably no one would have thought that the double-clutch transmission, which was once regarded as a street rat and was complained about by the major consumer population, would become one of the three mainstream transmissions at the moment, and its market share would even climb all the way, down to the entry-level grocery car, to the luxury sports car, you can see the figure of the double-clutch transmission.
Ordinary consumers may be more familiar with Volkswagen's DSG dual-clutch transmission, we have also had an in-depth technical interpretation, but volkswagen group's dual-clutch transmission is far more than DSG, he also has the main application in Audi models of S-Tronic 7-speed dual clutch, Porsche PDK dual clutch and so on.
(Audi A4L shift lever)
In this article, we will focus on the Audi S-Tronic7 speed double-disengagement, to see the development background of this dual-clutch, performance advantages, or what pain points exist.
First, the background of the launch of the Audi S-Tronic7
As a luxury brand owned by Volkswagen, Audi has always used AISIN or ZF AT transmissions and CVTs of earlier Schaeffler technology in the early days. (Now some Audi is also using ZF 8AT transmissions, mainly flagship models or performance sports cars, the specific models are as follows: Audi Q7, Audi Q8, Audi A8, Audi S4, Audi S5, Audi S6, Audi S7, Audi S8, Audi SQ5, Audi RS4, Audi RS5, Audi RS6, Audi RS7, Audi RS Q8).
However, with the completion of the replacement of A4L, Q5L, A6L and other models, the current domestic Audi models have achieved full coverage of dual-clutch transmissions. (However, the entire Audi series does not use a single type of transmission, such as the A3 and Q2L used 7-speed dry dual clutch).)
(Initially unveiled DL382 transmission)
Why Audi wants to fully popularize the dual-clutch transmission, we think there are several reasons.
First of all, we mentioned a truth in the article of Volkswagen double clutch - non-my family, its heart must be different, simply put, if a company does not have a spare parts manufacturer that produces transmissions or a transmission company that does not have indirect holdings, then the production capacity of the entire enterprise is deeply limited by the supplier.
When the production capacity is abundant, it is better to say that everyone has a share, and once the production capacity is tightened, then such spare parts suppliers must give priority to the supply of their own car companies (such as Toyota and Aisin), which is bound to affect the sales of non-own companies that are deeply bound to it.
(Aisin Seiki of Toyota Holdings)
Volkswagen, as one of the giants of the car company, certainly does not allow this to happen, so down to the Volkswagen brand, up to the Audi brand, have begun to adopt their own DSG dual-clutch transmission technology (why not use AT or CVT, because the Volkswagen Group has too few patented technologies in this regard).
Second, Audi as a high-end brand, its domestic models began to fully replace the double clutch, which can play a huge role in improving the dual clutch image of the Volkswagen Group, before in the Volkswagen Group's system, only Volkswagen's low-end models will use dual clutch, but now the high-end brand Audi has also begun to use, which is enough to dispel consumers' consistent prejudice that dual clutches are only equipped with low-end models.
Finally, the replacement of the double clutch naturally has a cost orientation, all capital is profit-seeking, Volkswagen is no exception, the double clutch is lower than the cost of high gear AT, which also means that Audi models have higher bicycle costs, even in the face of a competitive market, price cuts are more confident.
Second, what versions of the Audi S-Tronic7 are installed on which models
As mentioned above, with the audi A4L, Q5L, A6L and other models have completed the replacement, Audi's domestic models have achieved full coverage of the dual clutch, and the dual clutch version number currently installed on the above models is DL382 (of which the Audi A6L 3.0T version is DL382+, which can be understood as an enhanced version), mainly used in the MLB engine longitudinal platform.
(Volkswagen MLB engine longitudinal platform)
The key parameters of this transmission are shown below:
However, it is worth noting that the DL382 is not a new development, it is based on the DL501, and the main difference between the two transmissions is in the following aspects:
Versatility is different: the DL501 is mainly suitable for all-wheel drive models, while the DL382 can take into account both front-drive and all-wheel drive and hybrid functions.
The structure is different: the dl382 adopts a new type of large diameter equal diameter parallel structure clutch mechanism, and the unequal diameter of the dl501; in addition, the DL382 adds a dual-mass flywheel with centrifugal pendulum provided by Luk compared to the previous DL501, the function of this dual-mass flywheel is as follows: the engine will produce torsional vibration of the crankshaft due to rotational inhomogeneity during operation, and the torsional vibration is transmitted directly to the gearbox without vibration reduction treatment, and the gearbox will produce corresponding resonance vibration. The addition of this dual-mass flywheel can effectively suppress the noise and vibration generated by the engine at low speeds.
In addition, we look at the structural planing diagram (Audi Q5L transmission), the transmission of the two models is generally consistent in the general structure, and the main part is the input shaft, which is divided into the inner shaft and the outer shaft, which are connected to the engine by clutches 1 and 2 respectively. The input inner and outer shafts mesh with odd or even gears, respectively.
(DL501 Transmission)
However, the rear of the DL501 is connected to the central differential and the power is output to the front axle drive through a stout half shaft, while the DL382 is adapted to a timely four-wheel drive system, so the front end of the output shaft is directly transported to the front wheel through the spur gear drive group. The tail end of the output shaft is controlled by an electronically controlled multi-plate clutch to control the ratio of power delivered to the rear wheels.
(DL382 Transmission)
As we mentioned earlier, the DL382 also has two versions, of which the Audi A6L 3.0T version is DL382+, which also has some differences with the DL382, mainly by redesigning the clutch and mass flywheel, reinforcing gears and bearings, and improving the speed of the transmission electronic oil pump, while increasing the number of clutch friction plates, so that the transmission can transmit torque from the original 400N·m to 500N·m to meet the needs of greater power and torque output.
At present, Audi models equipped with the DL382 transmission are as follows: A7L, A6L, A4L, Q5L, Audi Q5L Sportback, Audi A5, Audi A7, Audi A6, Audi A4.
Third, the working principle of DL382, what are the performance highlights
3.1, the working principle
All dual-clutch transmissions work in a way that is ever-changing (Honda's 8-speed dual-clutch is a bit special, adding a torque converter), and in the Volkswagen DSG article we will go through in detail, and here it will be a simple one.
The dual-clutch transmission can be seen as a parallel arrangement of two MT manual transmissions, but it does not have a traditional clutch pedal, but uses advanced electronic systems and hydraulic systems to control the clutch like a standard automatic transmission, with one clutch controlling odd gears (first, third, fifth and reverse gears) and the other clutch controlling even gears (second, fourth and sixth gears). When the vehicle is put into one gear, the other clutch and the corresponding next gear are already in the ready state, as long as the current gear is separated, the next gear can be immediately connected so that the power transmission from the engine to the transmission can be shifted without interrupting.
(Dual-clutch transmission gear set structure)
In general, the advantages of dual-clutch transmissions lie in the speed of shifting and transfer efficiency, while the disadvantages lie in heat dissipation, smoothness and stability.
In view of the above disadvantages, how does Audi's DL382 do?
First of all, on the issue of heat dissipation, the DL382 gearbox is equipped with a dual-clutch module independent cooling system, which improves the heat dissipation capacity and stability of the gearbox through the folding layout of the dual-clutch module, and the volume of this transmission is further reduced due to the folding layout.
In order to do a good job of smoothness, Audi introduced a variable pressure electric oil pump and a gaseous pressure storage tank, which reduced the internal pressure of the gearbox and greatly improved the transmission efficiency, which also brought it a shift speed of 0.2 seconds, faster and smoother.
We looked at what the market said about the Audi Q5L after the DL382 transmission was replaced, and users generally believed that it was faster to change gears and more outstanding performance.
In addition, in terms of fuel saving, due to the faster gear change speed, the power loss is smaller, and the DL382 "adopts dry tank design and low pressure oil pump design, and the internal consumption of the system is reduced by 96%." Reducing the internal consumption by nearly half, significantly improving its transmission efficiency, so the fuel economy is also better, or take the Audi Q5L as an example, although its self-weight is close to 2 tons, but its comprehensive fuel consumption tested by the Ministry of Industry and Information Technology is only 7.4L hundred kilometers.
3.2 How to work with 4WD systems?
Compared with the DL501 mainly used in four-wheel drive, DL382 achieves a variety of drive modes, so how does it cooperate with the four-wheel drive system, we still take the Audi Q5L as an example.
At present, the current Audi Q5L series is equipped with a quattro ultra timely four-wheel drive system as standard, and this four-wheel drive system is divided into two parts: a central electronically controlled clutch differential and a rear electronically controlled clutch differential, which senses the body status through multiple electric controllers and notifies the corresponding four-wheel drive electronic control module.
Among them, the central electronically controlled clutch differential consists of a clutch, a scroll disc and a scroll rod, which is connected to the end of the output shaft of the previously mentioned Audi DL382 gearbox, and controls the power ratio transmitted to the rear wheel through the electronically controlled multi-plate clutch, while the electronic control actuator drives the worm disc through the worm to adjust the pressure applied to the multi-plate clutch, thereby controlling the transmission of power to the rear wheel.
The electronically controlled clutch differential is composed of a tooth-embedded clutch, a vortex rod, a separation arm, a locking lever and an electromechanical actuator. In front-drive mode, the center differential disengages the clutch and drives only the front axle; the four-wheel drive mode central differential clutch combines to deliver power to the rear axle. The rear clutch transports power to the left and right wheels of the rear axle via a tooth-mounted clutch combined with a scroll bar gear.
Fourth, how is the reputation
Although Audi has high hopes for this DL382 transmission, we have received quite a lot of complaints about this transmission from the feedback from the consumer market.
According to a complaint from a well-known third-party website, in the top 10 of the 2021 luxury car transmission complaint index, Audi's dual clutch occupies multiple positions, including the Audi A4L, Audi A6L, Audi Q5L and other models using DL382 are on the list.
Among them, the most complained about problem of Audi A6L by car owners is the failure of the electromechanical unit of the gearbox, which accounts for 49.10% of the problem, accounting for nearly half of the total, indicating that this problem is a common problem of audi A6L, and most of the problems exist in 2020 and 2021.
The Audi A4L transmission complaint index of 162, ranking second on the list. The main problem with the Audi A4L gearbox is the abnormal sound of the gearbox, which accounts for more than 40% of complaints, mainly concentrated in the 2019 and 2020 new models.
The main reason for the Audi Q5L to make the list is because the gearbox is frustrated, which involves a wide range and more 2020 models.
(2020 Audi Q5L)
We also took the Audi transmission failure as a keyword, searched on a search website, but the result was to jump out of nearly a million related terms, more specifically, some netizens have carried out relevant statistics: Most of the consumers who complained about the Audi transmission failure were the new Audi A6L purchased in 2019, and its fault performance was mainly concentrated in the Caton and abnormal sound between the 5th gear and the 4th gear, the shortest problem outbreak period was only 400 kilometers, and the longest problem outbreak period was only 20,000 kilometers.
This double clutch, which is specially created for the Chinese market, is indeed unsatisfactory from the perspective of word of mouth.
Fifth, compared with Porsche's double clutch, what are the characteristics of Audi double clutch?
At present, there are too many dual-clutch brands on the market, domestic, joint venture, many models are equipped with dual-clutch, wide comparison does not have great significance, so we chose the most famous Porsche PDK on the market to compare with Audi's double-clutch cooperation.
(Porsche PDK transmission)
Many friends are concerned about the essential gap between Audi's dual clutch and Porsche's double clutch, in fact, whether it is Audi or PDK's dual clutch transmission, the structure is actually similar, and their main gap lies in the use of materials.
PDK's gearbox is jointly developed and manufactured by Porsche and ZF, the cost is very high, the cost of a gearbox is close to a Golf vehicle, and Volkswagen's dual clutch is only a few thousand yuan. On the hardware side, the Porsche PDK uses alloy materials with better heat and wear resistance, and even uses two separate circulating oil circuits to help cool the gearbox, thus significantly improving the life and thermal decay performance of the gearbox.
In addition, in order to push the performance to the extreme, the PDK gearbox simply sets up two oil chambers, which are responsible for lubrication and hydraulic work (in general, the gearbox has only one oil chamber, and the oil inside undertakes all the work of lubrication and hydraulics).
The effect of this is also very obvious, in normal mode, PDK dual-clutch shift time is only 0.04 seconds, sports mode can reach 0.02 seconds, can withstand 50 consecutive ejections without attenuation, can withstand up to 1000N.md torque. All of this results in the PDK Dual Clutch – the best dual-clutch transmission in the world.
Write at the end:
The landing of the DL382 gearbox allows Audi to get rid of the constraints of ZF and Aisin transmissions, and truly realize self-production and self-sales, in addition, thanks to cost control, Audi models equipped with dual clutches can achieve higher bicycle profits. However, it is more regrettable that although the Audi DL382 transmission has achieved large-scale assembly, it has not achieved a win-win situation in word of mouth, and many car owners have many complaints about this transmission, and how to go further in word of mouth is the current Audi dual clutch compared to the BBA and other competitors that need additional consideration.