Torque converter, CVT, dual clutch or single clutch cars, what's the difference?

Audiophiles lament the digital age and its lack of deep vinyl warmth; cricket advocates rate the Twenty20 as a fat zero, and yet both forms of disdain are nothing compared to the loathing of driving enthusiasts who experience seemingly continuous moves towards automatic transmission dominance.

It doesn't matter that Formula 1 drivers make do with two pedals and a few paddle shifters, manual-driven motorists argue that life is meaningless without clutches and pedal dancing.

The fact, however, is that the vast majority of car buyers are happy to put their gearboxes in D for Do Small, and thus automatic shifters have reached almost ubiquity, with the Federal Chamber of the Automotive Industry (FCAI) claiming that automatic explains over 70 percent of new cars sold in Australia.

Frankly, it's surprising that this number isn't higher when you consider that less than 4% of cars sold in the US have a manual transmission.

You can't even buy a new Ferrari, Lamborghini or Nissan GT-R with a manual transmission.

This is not only due to laziness, but also because at the turn of the millennium, automatic transmissions became more and more perfect and economical, leaving the manual option for purists and the poor.

And the argument that you can't participate in driving without a shifter gets weaker every day when you think you can't even buy a new Ferrari, Lamborghini or Nissan GT-R with a manual transmission (and even the sportiest models Porsche). don't give you a chance).

So how did cars become an automatic choice and what makes them so enticing that people are willing to pay more for them?

Torque Converter

This is the most common automatic option found in the hugely popular Mazda lineup, as well as the more expensive Japanese brand Lexus.

Instead of using the clutch to turn the engine torque on and off from the gearbox, in traditional cars the transmission is permanently connected using a torque converter.

Torque converter automatics have the distinct advantage of high torque at low revs.

This slightly complex engineering solution pushes the liquid around the sealed housing with the help of the so-called "impeller". The fluid drives a turbine on the other side of the housing, which transfers the drive to the gearbox.

The torque converter automatic has the distinct advantage of plenty of torque at low revs, which is great for accelerating from a standstill and overtaking. Acceleration from a standstill is smooth, as is gear shifting, which was not always the case with jerky early 80s-style cars.

So how do you actually shift gears?

You may have heard the term "planetary gears" there, which sounds a bit grand, but basically refers to the gears arranged around each other, like the moons revolve around a planet. By changing which gears rotate relative to others, the transmission computer can change gear ratios and suggest gears that are suitable for acceleration or movement.

One of the traditional problems with torque converters has been that they are essentially inefficient due to the lack of a direct mechanical connection between the input and output shafts.

Modern "lock-up" torque converters include a mechanical clutch to provide more efficient clutching.

Add a set of paddle shifters to the steering wheel and modern torque converters can convincingly impress even their clutch-equipped brethren.

Single clutch gearbox

The next big technical step forward for the automatic transmission was the single clutch system, which is basically like a manual transmission with just two pedals.

The computer takes control of the clutch and adjusts the engine speed for smooth gear changes.

Or at least that was the idea, because in practice these automated manuals could take a while to disengage the clutch, shift gear and reengage, making them jerky and annoying, like a learner driver or a kangaroo hiding under your hood. . .

They have mostly been replaced and should be avoided when buying used.

The BMW SMG (sequential manual transmission) was a pioneer in this field, but while technical executives loved it, many people were driven mad by its ineptitude.

Some cars still struggle with the single clutch system, such as Fiat's Dualogic transmission, but they have mostly been replaced and should be avoided when buying used cars.

Dual Clutch Transmission (DCT)

The dual clutch system sounds like it should be twice as good, and it is.

These advanced gearboxes, perhaps most famously used by Volkswagen with its DSG (Direkt-Schalt-Getriebe or Direct Shift Gearbox), use two separate sets of gears, each with its own clutch.

An efficient modern car with DCT can change gears in just milliseconds.

In a seven speed transmission system, 1-3-5-7 would be on one link and 2-4-6 on the other. This means that if you're accelerating in third gear, fourth gear may already be selected, so when it's time to shift, the computer simply releases one clutch and engages the other, resulting in an almost smooth shift. An efficient modern car with DCT can change gears in just milliseconds.

The VW system is fast, but the dual-clutch gearboxes used in cars like the Nissan GT-R, McLaren 650S and Ferrari 488 GTB provide staggeringly fast shift times and almost no torque loss in between.

As difficult as it is for the purist to swallow, it also makes them faster and easier to manage than any manual.

Continuously Variable Transmission (CVT)

This may sound like the perfect automatic solution, but the CVT can be annoying for some people.

The CVT does exactly what it says on the label. Instead of shifting between a given number of predetermined gears, the CVT can change gear ratios on the fly almost indefinitely.

Imagine a traffic cone mounted on an axle, with a second empty axle parallel to the first. Now put the elastic on the axle and cone.

CVTs can keep the engine running at peak efficiency

If you move the rubber band up and down the traffic cone, you will change how many times the empty axle must rotate to complete one rotation of the cone. By moving the bar up and down, you change the gear ratio.

Since the gear ratio can be changed without changing gears, CVTs can keep the engine running at peak efficiency.

In practice, this means that when you accelerate in a car with a CVT, it makes a constant whirring sound instead of the traditional up and down revs.

It's very economical, but doesn't sound as exciting as the engine should. Again, this is a purist opinion and some people don't notice a difference at all other than the fuel pump.

So what to choose?

Modern automatics provide better fuel economy than manuals due to the greater choice of gear ratios. Most manual transmissions have six forward gears, although the Porsche 911 offers seven.

Modern dual-clutch systems use seven gears, torque converter cars go up to nine, and CVTs can create an almost infinite number of gear ratios, meaning they provide the best fuel economy.

With shift speeds that confuse the fastest manual driver, the automatic can also accelerate faster.

It's not just ultra-fast dual-clutch systems; ZF's nine-speed torque converter transmission offers gearshifts that are said to be "below the threshold of perception".

Many automakers are moving away from manual transmissions entirely.

It's like curtains for humble leadership; which has become a slow, thirsty, and left-foot-consuming option.

Many automakers are ditching manual transmissions entirely, so it's not even a base model option to save a few bucks.

It's hard to believe, but manual transmission driving may seem as absurdly retro to your grandchildren as vinyl records are today.

What are your transmission preferences? Are you still driving a mechanic? Tell us what you think in the comments below.