What is A Dual Clutch Transmission?

The Dual Clutch Transmission (DCT) Sits in Between Automatic and Manual

More mechanically, dual clutch transmissions don’t have a torque converter like a typical automatic transmission. Without the torque converter, a DCT instead shifts gears more similarly to a manual transmission. The difference from a manual transmission then is that a DCT uses two output shafts instead of one.

How Does a DCT Work?

We already know from the name that a dual clutch transmission uses two clutches – but how does that work? The two clutches operate concentrically, so that one sits inside the other with two input shafts. This way, operation can switch back and forth between the two with the non-active clutch pre-selecting the next necessary gear.

Essentially, Two Gears Are Selected Simultaneously Using Shift Forks for Quick Transitions

While your active gear is in use, the second clutch is also predicting which gear will be next and pre-selecting it, essentially meaning two gears are always selected at any given time. Another difference from a manual transmission is the actual operation. This type of clutch would not work if gears were selected mechanically as they are in a manual transmission. Instead, shift forks powered by pistons are able to quickly engage and disengage as necessary to change gears.

Combined Ease to Drive with Ability to Control Power

Because there’s no mechanical gear shift, the driver isn’t required to shift gears up or down as they drive and change speeds. There also is no clutch pedal, so you won’t end up accidentally killing the engine in the middle of traffic. At the same time, if you want more control over your car’s power, such as on icy or snowy roads, you can change driving modes to take control over your gear. In this mode, you’ll typically be able to change gears with either a set of paddles on the steering wheel or a gear shift by the center console.

Quicker Gear Changes

Another noticeable advantage is quick, smooth gear changes. This is really the key benefit and reason behind the development of this type of transmission. Because of it, the driver and passengers in a DCT car will enjoy a smoother ride, feeling each gear change much less than you might in a manual or automatic transmission vehicle.

Faster Acceleration

A side benefit to quicker gear changes is faster acceleration. There’s much less pause where you lose power during each gear change, so you’ll experience a smoother, quicker acceleration. This is another reason why dual clutch transmissions work well in smaller, sportier cars.

Better Fuel Economy

Another side benefit of quicker gear changes is better fuel economy. Whenever you have a pause where power is temporarily lost, your engine will have to work a bit harder once power is restored to pick up speed again. This will cost you gas mileage over time. By maintaining more consistent power through gear changes, you’ll notice your gas tank lasting a bit longer.

Delays During Initial Acceleration & Downshifting

The biggest downside is a delay in acceleration when initially starting up from being parked or idling. This delay in engaging first gear can be bothersome, especially to drivers unfamiliar with this type of transmission system. However, many drivers are able to adjust their habits and newer DCTs have improved with technology. There are also sometimes delays with downshifting when it happens rapidly. It can take longer than expected for the transmission to catch up to where it should be when having to change gears more rapidly.