How Durable is the BYD 6-Speed Wet Dual Clutch Transmission?
2 Answers
BYD's 6-speed wet dual clutch transmission is reliable and durable. Here is an extended introduction about BYD's dual clutch transmissions: 1. Dry dual clutch: The 6-speed dry dual clutch can withstand a maximum torque of 250 Nm. When paired with a 1.5T engine, this dry dual clutch was found to be relatively unstable. Subsequently, BYD matched this 6DT25 with a naturally aspirated 1.5L engine that has much lower torque, and eventually discontinued the 6DT25 dry dual clutch. Although this dry clutch was not entirely successful, the experience gained was invaluable, providing crucial foundational data for BYD to develop better products in the future. 2. Wet dual clutch: The 6-speed wet dual clutch can handle a maximum torque of 350 Nm and is paired with a 2.0T engine, making it more stable. BYD has been cautious with power matching, opting to use this 6DT35 wet dual clutch with 1.5T engines, such as in the Song series and 1.5T Qin series. With the 1.5T engine's maximum torque of 240 Nm and the 6DT35's capacity of 350 Nm, there is a torque margin of over 100 Nm. Additionally, since both the ECU and TCU are produced in-house by BYD, the matching is excellent. The transmission performs well in various scenarios: strong starting creep, smooth shifting, delayed upshifting on slopes, and automatic gear changes based on speed when coasting or going downhill without throttle input. BYD has continuously upgraded and optimized this transmission, such as switching to Schaeffler-made clutch plates instead of in-house production.
I've been driving a BYD car for several years, and the overall durability of this six-speed wet dual-clutch transmission is quite reliable. The wet design uses oil cooling, which is much better than dry dual-clutch transmissions, reducing the risk of overheating and deformation. This greatly benefits the lifespan of the clutch plates. Even during occasional city traffic jams, the transmission works continuously without much noticeable jerkiness. However, a word of caution: if you have poor driving habits, such as frequent hard acceleration or prolonged semi-engaged clutch states, it will wear out faster. I recommend regular transmission oil changes. Generally, it can last between 50,000 to 100,000 kilometers without issues—my car has already clocked 80,000 kilometers and is still running fine. In short, don’t worry too much; BYD has made significant improvements in later models, making them far more durable than the early dry dual-clutch versions.