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Blurring the Connection

September 4, 2011 by Matt

Dual Clutch Transmission DSG PDK SMG

The line between automatic and manual transmissions is losing definition. Whereas before a car buyer had exactly two choices—three-pedal manual or torque-converter automatic (perhaps with a manumatic shift mode, but still a slushbox)—in the past 10 years “flappy paddle gearboxes” of the single- and dual-clutch variety have arrived to complicate the issue. This raises the question: Are they manual or automatic? Yes, in most cases, their purpose is to replace a manual transmission, but set to fully automatic mode, the seamlessness of their shifts (dual-clutch especially) can rival the best slushboxes on the market. And they lack a traditional third pedal. So what are they?

In a their March issue, Car and Driver took a stand, switching from calling dual-clutch transmissions (e.g. VW/Audi’s DSG, shown above) “dual-clutch manuals” to “dual-clutch automatics.” They wrote:

Our conclusion is that we need to update our definition and classification of both types to reflect how they perform, instead of trying to distinguish them by the hardware they employ. Automatics and dual-clutch gearboxes both have the ability to send power to the wheels during upshifts, something no manual gearbox can do. For this reason, dual-clutch transmissions will now be known as dual-clutch automatics in Car and Driver.

Do you buy it? Should “how they perform” be the pivot point of the terminology in dispute? Or should we rather classify transmissions as belonging to one camp or the other based on how they’re predominantly used by the driver? In other words, for better or worse, to an enthusiast, the words “manual” or “automatic” do more than convey mechanical functionality—they communicate intent, and it just doesn’t sound right to call, for example, the fire-breathing BMW M3 GTS‘s gearbox an automatic, dual-clutch or no. What say you?

Filed under: Miscellaneous, Technical


  1. John D says:

    To me it’s simple. If the driver has complete control and discretion about exactly *when* the gear change takes place, and has to set that chain of events in motion directly for each and every gear change, it’s a manual. Whether or not the clutch is automatic or manual really has no bearing on the functional designation of the transmission itself…but it is straying from the original concept of the ‘manual transmission’ experience.

    I admit there seems to be no correct answer to this conundrum. Personally, I prefer both a manual transmission coupled to a manual clutch…but I am not so narrow minded as to cry heresy when technology begins meddling and changing the particulars of who does what. So what if a gear has been spun up and the clutch mechanism is taken care of by some other process? If the driver is the one in complete control over when to change out of one gear and into another (and there is no fail safe or automatic gear change backup system in place), it’s a manual transmission. The name says it all. Just because (until recently) it’s been assumed and necessary to have a manual clutch in conjunction with a manual transmission doesn’t mean that it has any bearing on the matter.

    I vote that we call the manual clutch/manual transmission combination a ‘traditional manual transmission’ so that others may not be confused or outraged at how technology has displaced their understanding of a ‘row your own gears’ drivetrain. The ‘manual transmission’ designation should be confined to describing the function of the transmission alone, not the type of gearshift utilized or even the intelligence of it’s inner workings.

  2. John D says:

    And in regards to C/D’s definition, I don’t think ‘how’ it delivers the power to the next gear is the issue. It’s all about the who and when. Automatics have their own brain. In a manual transmission the driver is the brain without which the transmission is incapable of selecting it’s own gears. Everything else is irrelevant to the discussion.

    Now exactly *which* type of manual transmission you prefer is a different topic entirely. There is a wide variety under any definition (including selection input device, clutch type, gear pre-selection, etc).

    • Matt says:

      All good points. As you well know, part of what complicates the issue is the fact that “manumatic” slushboxes have been available for some time (believe Porsche’s Tiptronic was one of the first in the early ’90s). The driver has control over when those transmissions shift as well. I know you kind of addressed that issue in your reply when you specified “no automatic gear change up or other failsafe,” but a lot of flappy-paddle ‘boxes have that function…

      Complicating my idea of classifying transmissions by intent is the fact that dual-clutch transmissions are beginning to be offered in luxury sedans and other cars where they’ll be left in “auto” mode 95% of the time. Are we really going to call exactly the same hardware a manual transmission in an M3 and an automatic in a 7-series? It’s silly.

      Interestingly, Wikipedia actually has three categories: Manual, automatic and semi-automatic. Single- and dual-clutch flappy paddles fall in that last category. I kind of like their system.

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