Though a dual-clutch transmission is missing a clutch pedal, it’s hard to classify it as an automatic. While most automatic transmissions rely on either a torque converter or, if it’s a CVT, a system of pulleys, the dual-clutch transmission uses clutch plates, like a manual transmission. A dual-clutch gearbox, by contrast, uses two clutches, but has no clutch pedal. Sophisticated electronics and hydraulics control the clutches, just as they do in a standard automatic transmission. In a DCT, however, the clutches operate independently. The dual clutch transmission (DCT), also referred to as a double- or twin-clutch transmission, combines the best of both manual and automatic transmissions into a hybrid that requires no input from the driver to shift gears, provides smooth and fast shifting, and operates more efficiently than either a manual or an automatic transmission.
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Many drivers treat their car’s dual-clutch transmission in the same way that they would drive a car that had an automatic transmission. But, a dual-clutch transmission is more like a manual transmission than automatic. And if you don’t treat it properly, you could permanently damage it.
Some of your current driving habits could ruin a dual-clutch transmission. If you’re doing any of the following and your car has a DCT, cut it out!
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Habits to avoid so you don’t ruin a dual-clutch transmission
Stop taking your foot off the brake
Dual Clutch Automatic Transmission Fluid
If you have a tendency to let your DCT sit without applying the brakes, such as waiting in traffic or at the foot of an incline, you could be wearing out the clutch pack. When the brakes aren’t applied, some DCTs will make the clutches continually slipping to keep you in place. This depends on how your transmission operates, but you could be putting extra heat and wear on the clutch pack.
Stop putting the car in neutral
Those who are used to driving stick shifts might have a habit of putting their car in neutral when they’re fully stopped at an intersection. You don’t need to do this with a dual-clutch transmission. The car will intuitively release the clutches when you’re braking, so there’s no point switching out of Drive.
If you do ever put the car in neutral, keep the brake depressed when shifting into and out of neutral to protect the clutch.
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Dual Clutch Automatic Vs Automatic
Stop launching improperly
In sportier cars with dual-clutch transmissions, drivers like to launch from a stand-still, but doing so incorrectly can severely damage the gearbox and clutch disks. Don’t hold the brake pedal while you’re revving the gas because the clutch will take damage trying to move the car while you’re fighting it with the brakes. In general, never accelerate the engine when the brakes are applied.
Stop keeping the car in place by accelerating
If you’re sitting on an incline, don’t repeatedly tap the acceleration pedal to keep your position. The same goes for putting the car in reverse and accelerating backward to stop from rolling down a hill. Both practices will quickly overheat the clutch. Use the brakes instead.
Clutch behavioral logic and functions vary from manufacturer to manufacturer, so research your specific model to find out how to properly operate. Your car’s owner’s manual will have a lot of information on proper handing to not ruin a dual-clutch transmission.
Dual Clutch Automatic Transmission
Sources:Engineering Explained, 2014 Hyundai Veloster owner’s manual
Dual Clutch Automatic Transmissions
Aaron is unashamed to be a native Clevelander and the proud driver of a Hyundai Veloster Turbo (which recently replaced his 1995 Saturn SC-2). He gleefully utilizes his background in theater, literature, and communication to dramatically recite his own articles to nearby youth. Mr. Widmar happily resides in Dayton, Ohio with his magnificent wife, Vicki, but is often on the road with her exploring new destinations. Aaron has high aspirations for his writing career but often gets distracted pondering the profound nature of the human condition and forgets what he was writing… See more articles by Aaron.
Dual Clutch Automatics
The dual clutch transmission (DCT), also referred to as a double- or twin-clutch transmission, combines the best of both manual and automatic transmissions into a hybrid that requires no input from the driver to shift gears, provides smooth and fast shifting, and operates more efficiently than either a manual or an automatic transmission. Its unique configuration is known as a semi-automatic transmission. It uses two separate clutches, one which engages even numbered gears in the transmission while the other engages the odd numbered gears. While one gear, third gear for example, is engaged, the clutch has the next gear, possibly fourth gear if the driver is speeding up, ready to go so it can instantly switch from third to fourth without losing any of the engine's power and without requiring the driver to press down the clutch pedal as he would need to in a manual transmission car.
Since the car's driver isn't required to press a clutch pedal to shift gears, it would seem the dual clutch transmission is automatic. Yet it is actually semi-automatic. Electro-hydraulic fluid is used to engage and disengage the clutches. This fluid forces the clutch disk against the flywheel of the engine and the power spins the car's wheels. When the car slows, sensors send less fluid to the clutch and it disengages because the fluid's force is not strong enough to hold it against the flywheel.
Two clutches make the dual clutch transmission possible. While one gear is engaged, the clutch prepares to switch to the gear on the opposite clutch. Since one clutch holds the odd numbered gears and the other the even numbers, the clutches constantly switch back and forth and the transition from one to another happens so quickly the driver never feels the car change gears.
Advantages of the dual clutch transmission include more efficient performance and faster shifting speeds. Since the next gear is already ready to switch into, the change occurs almost instantly and the shift is smooth. No engine power is lost, as it is in automatic transmissions using torque converters to engage and disengage the engine. The torque converter is similar in principle to the electro-hydraulic fluid, but loses some of the power from the engine when engaging and disengaging.
Disadvantages of the dual clutch transmission include its high cost and the complexity of its parts. Cars utilizing this type of transmission cost more and repairs take more effort due to the extra parts and how they are aligned with one another. With more parts, there are more problems that can arise.