Why is the dry dual-clutch transmission not good?
3 Answers
Dry dual-clutch transmission has the following disadvantages: 1. It has insufficient heat dissipation, making it unsuitable for frequent starts, prolonged low-speed driving, or stop-and-go traffic, which can lead to clutch overheating and even malfunctions; 2. Since it does not use a torque converter and cannot achieve the semi-engagement action of a manual transmission, for small-displacement engines, the dry dual-clutch transmission may exhibit insufficient torque at low speeds. Dual-clutch transmissions come in wet and dry types. A dry dual-clutch transmission refers to a dual-clutch transmission where the clutch plates are not immersed in transmission oil; in contrast, the clutch plates of a wet dual-clutch transmission are immersed in transmission oil.
The main issue with dry dual-clutch transmissions is heat dissipation. Since they are not immersed in oil for cooling, they perform fine on highways but suffer in city traffic, especially during rush hours. The constant stop-and-go driving causes the clutch to repeatedly engage in partial friction, akin to sanding with sandpaper, causing temperatures to skyrocket. When the transmission overheats, it triggers a protective shutdown, potentially leading to sudden loss of power—a terrifying scenario. A friend’s Volkswagen, for instance, abruptly lost power while climbing a garage ramp, nearly rolling back into a wall. Additionally, the fast gear shifts come with a downside: noticeable jerking during low-speed follow-up driving, making the ride uncomfortable. Repairs aren’t cheap either, making wet dual-clutch or traditional AT transmissions more durable choices.
I think the biggest pitfall of dry dual-clutch transmissions lies in stop-and-go traffic. Initially, I found the gear shifts incredibly crisp, but prolonged use revealed some annoying issues. Being stuck in city traffic for half an hour with frequent pedal movements causes constant clutch plate friction and heat buildup. When temperatures get too high, the system forces a protective cooldown—I've experienced three sudden instances where pressing the accelerator didn't move the car, making me nervous at red lights now. The low-speed jerkiness is particularly noticeable too, especially during 1st-to-2nd gear shifts, creating a rocking sensation for passengers. Maintenance bills are even more frustrating—my last clutch assembly replacement cost over 8,000 RMB, while my friend's similarly priced CVT vehicle only needed a transmission fluid change once.
