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Fewer than 3% of cars sold in the U.S. have manual transmissions

latimes.com

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Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#191

Post by dogma1138 »

nostrademons wrote: post #168
sshanky wrote: post #128

Earlier quoted context omitted.

In modern cars, disengaging the clutch (or using neutral) when coasting (toward a stop or down a hill) is less efficient than staying in gear. This is because it takes some fuel to keep the engine idling, where staying in gear allows the computer to completely cut fuel flow, as long as the forward motion is keeping the engine turning.

How modern is modern? I could believe this of my 2009 Honda Fit, but I'm fairly certain that my dad's '92 Civic, '99 Civic, and '92 Accord got better mileage when coasting with the clutch disengaged.

92 was 25 years ago, this isn't a modern car, it should not be on the road if you care about economy and road safety.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#192

Post by jfitbsidbfb »

nostrademons wrote: post #168
sshanky wrote: post #128

Earlier quoted context omitted.

In modern cars, disengaging the clutch (or using neutral) when coasting (toward a stop or down a hill) is less efficient than staying in gear. This is because it takes some fuel to keep the engine idling, where staying in gear allows the computer to completely cut fuel flow, as long as the forward motion is keeping the engine turning.

How modern is modern? I could believe this of my 2009 Honda Fit, but I'm fairly certain that my dad's '92 Civic, '99 Civic, and '92 Accord got better mileage when coasting with the clutch disengaged.

My 1998 Saturn noticeably cut fuel on deceleration, it was easy to tell since the exhaust system was perpetually breaking

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#193

Post by dogma1138 »

edoloughlin wrote: post #169
Reason077 wrote: post #101

Earlier quoted context omitted.

Modern manual cars have start/stop technology too. However, it's more convoluted to use. You have to engage the clutch, put the shifter in neutral, and release the clutch again. Compared to automatic where you just have to hold your foot on the brake pedal. Stop/start reduces fuel consumption on test cycles like NEDC for both automatics and manuals, but I'll bet in the real world the benefit is mostly seen with autom…

However, it's more convoluted to use. You have to engage the clutch, put the shifter in neutral, and release the clutch again This is how you should drive if you know you're going to be stopped for more than a few seconds. 'Convoluted' doesn't come into it - it's the default.

I want to see the people who cycle the clutch twice at a red signal.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#194

Post by jfitbsidbfb »

Neil44 wrote: post #181
vmarsy wrote: post #104

Earlier quoted context omitted.

>when automatic transmissions are consistently outperforming humans at fuel efficiency Do you have data to back this up? Unless you're driving a dual clutch "dry" transmission or a CVT, because of Physics, an automatic transmission will always be less efficient. The Automatic transmission Torque converter [1] will waste some of the energy provided by the engine, especially with city driving. Also, most automatic cars…

Those things have not been true of automatics for the last two or three generations. They have clutches inside the torque converter, they can block shift. But it is only the latest generation of gearboxes that return better economy figures than manuals. Until very very recently auto boxes were indeed much worse for economy.

The TC only locks under light load on the highway, and isn't 100% effective there because the hydraulic fluid still produces a lot of drag.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#195

Post by dx034 »

tdkl wrote: post #171
dx034 wrote: post #72

Earlier quoted context omitted.

Not sure if that's the case. While I love manual transmission, I would rather argue that it is more dangerous as you're often forced to have one hand away from the steering wheel, which makes it harder to react quickly.

Number of hands on the steering wheel has nothing to do with reaction time.

No, but it determines how well you can steer. Especially in sharp turns you usually have to shift down/up. If there's an obstacle (perhaps a person), both hands on the wheel will give you more room to steer in both directions. You'll be much more limited with one hand.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#196

Post by semi-extrinsic »

nostrademons wrote: post #168
sshanky wrote: post #128

Earlier quoted context omitted.

In modern cars, disengaging the clutch (or using neutral) when coasting (toward a stop or down a hill) is less efficient than staying in gear. This is because it takes some fuel to keep the engine idling, where staying in gear allows the computer to completely cut fuel flow, as long as the forward motion is keeping the engine turning.

How modern is modern? I could believe this of my 2009 Honda Fit, but I'm fairly certain that my dad's '92 Civic, '99 Civic, and '92 Accord got better mileage when coasting with the clutch disengaged.

Basically any car that has electronic fuel injection does this. So at least the '99 Civic definitely does it.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#197

Post by Ntrails »

nostrademons wrote: post #168
sshanky wrote: post #128

Earlier quoted context omitted.

In modern cars, disengaging the clutch (or using neutral) when coasting (toward a stop or down a hill) is less efficient than staying in gear. This is because it takes some fuel to keep the engine idling, where staying in gear allows the computer to completely cut fuel flow, as long as the forward motion is keeping the engine turning.

How modern is modern? I could believe this of my 2009 Honda Fit, but I'm fairly certain that my dad's '92 Civic, '99 Civic, and '92 Accord got better mileage when coasting with the clutch disengaged.

Think about what is required to turn the engine over and prevent stalling.

-When the clutch is engaged whilst going down hill the wheels turn the engine. No Fuel Required. -When the clutch is disengaged the engine has to turn itself over - which needs fuel.

*Disclaimer, i'm sure carbourettas (sp?) could well be doing weird ass things so whilst conceptually the above holds they may well be different.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#198

Post by VMG »

skrause wrote: post #158
VMG wrote: post #122

Earlier quoted context omitted.

Very similar situation in Germany. I think the misinformation could be an historical artifact from times when automatic transmission technology was in early stages.

I don't think there is a lot of misinformation in Germany. I'm German and I simply buy manual transmissions because they are a lot cheaper and I know a lot of people who are they same. I really would prefer an automatic transmission, but spend an extra 2000 euros for that bit of extra comfort? No thanks.

I was referring to the misinformation about higher fuel efficiency of manual compared to automatic. I heard it too in driving school.

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#199

Post by 0xAA55 »

I recently went to the ends of the earth to get a 2016 manual VW sportwagen in the US -- but it was possible after going to dealerships looking at me like I was insane.

Shifting around in my BMW e36 5 speed will always be one of my greatest pleasures People complain about traffic, but I feel the opposite. I mean, in an auto if you see a spot to cut into you are forced to floor it to force the car in a low enough gear -- it feels like the car is suffering vrrrAHHHHHHHHER

Re: Fewer than 3% of cars sold in the U.S. have manual transmissions

#200

Post by henrikschroder »

kalleboo wrote: post #180
henrikschroder wrote: post #160

Earlier quoted context omitted.

I should probably have qualified my statement with an "over time, in real driving conditions". In a measured test, with a skilled driver, who does the right thing for the entirety of the test, it is most likely that he or she will be more efficient with a manual transmission than with an automatic. However, in real life, for real humans, over a longer period of time, the drivers with modern automatic transmissions wi…

I'd love to see some kind of study that went deep into how the results pan out over a certain population and why. My own anecdote is that I'm a better driver in a manual. I'm a lazy driver, and lazy in a manual means avoiding stopping/gear changes by anticipating green lights and so on. Being lazy in an automatic results in more stop and go for me because it's no more effort. I could be as efficient in an automatic,…

Many modern cars are completely drive-by-wire, and have a mode selector inbetween your controls and the car, which forces you into more fuel-efficient driving, e.g. ignoring if you push the speeder all the way down, and accelerating the car at an efficient pace instead. The more sensors and processing you get in a car, the better the car can be a this.

Other modern cars have an "eco display" or similar, which gamifies the experience. My previous car had some progress bars for different aspects, and I spent several boring commutes trying to get to a perfect 100%. (I did it once, I was so happy! Usually only got it to 98% before I hit the city and got stuck in traffic again)

Making automatics more efficient is a technological optimization problem. Making manuals more efficient is a human skill problem. I know which side I'd bet on in the long run. (Hint: Not the human)

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