An Analysis of Correcting Ford powershift with Actual Performance

　　　　Powershift, once regarded as the technology of transmission terminator, seems to have been in the forefront recently. A series of problems caused by Volkswagen DSG dual clutch make people anxious about the quality of the dual clutch while they are eager for the dynamics brought by it. The PowerShift 6DCT250 gearbox of Ford New Focus and Volkswagen DSG are both dry dual-clutch gearboxes. Although the structures of the two gearboxes are obviously different, will Ford’s PowerShift gearbox also encounter the problems of Volkswagen DSG? Let’s analyze Ford powershift 6DCT250.

　　　　The Ford 6-speed powershift PowerShift 6DCT250 is mainly used in the new Focus models. According to the manufacturer’s introduction, the gearbox numbered 6DCT250 uses internal double clutches and optimizes some other components. In fact, in popular terms, two manual transmissions are intelligently combined, and at the same time, the electronic system is used to automatically select the required gear instead of the driver. According to our experience, because the manual gearbox is hard-connected, the similar Ford PowerShift gearbox also has the same problem as the manual gearbox — — Slight shift frustration, but this frustration is completely less obvious than the best manual gearbox, almost imperceptible. Manual gearbox can properly adjust clutch operation and select shift timing to reduce frustration, while 6DCT250 is an automatic gearbox, so it is all operated by computer. However, due to the limitation of the technical structure itself, this sense of frustration can not be completely eliminated, but it will not be detected at all in daily driving, and it provides the general driving pleasure of manual transmission.

　　　　Why use this transmission when there is a sense of frustration? The reason is that this gearbox has the advantages of small power loss, direct acceleration and low fuel consumption. It can not only give drivers direct control pleasure, but also adjust gears conveniently and automatically, reducing fuel consumption, which can be described as a solution with both manual and automatic gearboxes. According to the survey, more than 70% netizens said that the fuel consumption of the new Focus with dry dual clutch was excellent, and the actual fuel consumption of the dual clutch version was far ahead of the automatic transmission model at the same displacement, even close to the fuel consumption of the manual transmission.

【 Ford dry powershift 6DCT250 】

　　　　So what about the Volkswagen 7-speed DSG? Is it just one more forward gear than Ford’s 6DCT? According to the engine disassembly diagram, we can see that although they are both dry powershift, the main components are also provided by LuK Company under Schaeffler. However, the gearboxes of the two companies were designed separately by LuK Company according to their needs. In addition to the same manufacturer, Ford and Volkswagen’s dual clutch gearboxes are completely different modules. The output shaft of the Volkswagen DSG transmission numbered DQ200 is a three-axis layout, while the Ford 6DCT250 uses a dual-output shaft design. Even on the 7-speed dry dual-clutch gearbox planned by Gertrak in the future, it is still a dual-output shaft design.

[Volkswagen Dry powershift 7DSG]

　　　　In addition, the biggest difference between the two transmissions lies in the control mechanism. On Volkswagen powershift, the clutch and shift mechanism are controlled by an electronically controlled hydraulic system, and the gearbox and control module of Volkswagen DQ200 are two independent oil spaces in oil circuit design, unlike other automatic hydraulic transmissions or wet powershift, which use the same oil as gear oil and hydraulic oil at the same time. Later, it was the formula of hydraulic oil code G004000 that led to the later "crystallization", which led to a series of problems such as the failure of slide valve box. Ford’s 6DCT250 uses a motor to drive the clutch and shift process, and does not use Volkswagen’s hydraulic device. This not only fundamentally avoids the failure of Volkswagen’s transmission, but also becomes simpler and more compact in structure.