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I used to think automatics were horrible (I live in the UK, drove manual for 15 years) then I got one... In terms of fuel economy, isn't it just a matter of ti

I used to think automatics were horrible (I live in the UK, drove manual for 15 years) then I got one... In terms of fuel economy, isn't it just a matter of time before automatics become as economical (then probably more economical) than manuals? Even without anticipating future events? Driving efficiently feels like something a computer could optimise for and that a human has no natural advantage doing.

josephlord 13y ago
A traditional automatic with a torque converter will always be less efficient I but the newer dual clutch models can probably match (or even exceed through better gear selection) the efficiency of manuals.
Marazan 13y ago
Without being able to determine future road conditions then automatics can't guarantee being in the "right" gear for the up coming section of road. Be that due to traffic, grading, weather, banking, sharpness of corner etc. My go to example is the insanity of junction 15 of the m8, that loop onto the west bound motorway is a 270 degree corkscrew rising 30 feet with a diameter of 55 yards onto a 5 lane motorway where I need to go from the left hand lane to the right hand lane (as there are entrance and exit lanes on both the inside and outside of the motorway at that point). A current automatic engine wouldn't know what was the right thing to do in that situation ( https://www.google.co.uk/maps/@55.8672951,-4.2358853,374m/data=!3m1!1e3 https://www.google.co.uk/maps/@55.8672951,-4.2358853,374m/da... ) To determine all of that you'd basically be at the level of self-driving car. Which would be awesome.
- gambiting 13y ago
  >> Without being able to determine future road conditions then automatics can't guarantee being in the "right" gear for the up coming section of road. Be that due to traffic, grading, weather, banking, sharpness of corner etc. Latest Rolls-Royce Wraith does exactly that - it uses the GPS map data to change gears in advance as it is approaching a turn in the road. I am sure that this technology will be available in ordinary cars soon enough.
  - emidln 13y ago
    An augmented version of this technology (applying known map data plus sensor data) is a huge piece of the self-driving car.
- dagw 13y ago
  Your GPS already knows where you want to go, what the road ahead looks like and often even the current traffic situation. I imagine writing some semi-smart software that hooks up that info to the automatic gearbox to give it hints about what to do wouldn't be outside the realm of possibility and no doubt a lot easier than self-driving.
  - gambiting 13y ago
    There are cars which already do exactly that: http://www.dvice.com/2013-3-7/new-rolls-royce-looks-ahead-gps-pick-right-gear http://www.dvice.com/2013-3-7/new-rolls-royce-looks-ahead-gp...
- ecopoesis 13y ago
  Or just buy a Nissan Versa today: http://www.edmunds.com/fuel-economy/five-myths-about-stick-shifts.html http://www.edmunds.com/fuel-economy/five-myths-about-stick-s... Manuals have better fuel usage then automatics is a myth for recent cars, no fancy self driving needed.
  - Marazan 13y ago
    That's based on the official figures. No-one gets the listed MPG ratings in real life and automatics suffer worst than manuals for under-shooting the official mpg rating.
  - sitharus 13y ago
    I just purchased a Toyota Yaris. The official figures for the 1.3L engine give 5.7L/100km for manual and 6.3L/100km for the automatic. Now in a high-end car with a sequential gearbox this is different, but for a small town car when you'll be doing a lot of starts and stops you'll see the losses on the hydraulic coupling.
- mschaecher 13y ago
  I have a feeling being able to determine immediate near term road conditions is a 1.0 feature for self-driving vehicles? Waze-style technology + GIS + networking with other vehicles + weather data (if you look, there is already tons of small weather monitoring stations all over major). thoroughfares). I mean many vehicles within the last handful of years have automatic traction control that can react faster to a real time change in road conditions than any human could ever hope too. A lot of the stuff I mentioned above is just extending that foresight out further so as to not be so jarring.
- grmarcil 13y ago
  I'm a die-hard manual fan, so you have my sympathy here. That said, I think current automatic technology is at the point where it can handle your go-to example with no problem. Yes the responsiveness of your base-level Toyota/Honda/Ford automatic transmission is going to be lacking versus a manual, but step up to a Mercedes or BMW double clutch automatic gearbox, or just go straight to the top of the automatic heap with Porsche's PDK transmission, and I think you will find all of them quite performant, even without paddle input. To preempt the "but you have to own a porsche for that!" responses, I'm not saying this is cheap, I'm just saying it is not limited by the available technology, just cost.
bananas 13y ago
You'd think so but I get 7mpg more than the best rated Toyota hybrid which is supposedly the most efficient thing out there. Bear in mind I drive a 6 year old 1.3L diesel Fiat van converted to a people carrier which is as aerodynamic as a shed. It also has 3 children, a buggy and a pile of crap in it. Perhaps a computer could optimise this better but I doubt it. The computer and automatic box just goes when you push the pedal down. The driver isn't connected to it and feeling what it's doing and understanding the power curves.
- selmnoo 13y ago
  > You'd think so but I get 7mpg more than the best rated Toyota hybrid which is supposedly the most efficient thing out there. You sure about that? Because I easily get about 70 mpg on my Prius (C class) when I'm supermiling in the city. Granted it's not as efficient on the highway, and unfortunately I do have to do a lot of highway travel. I can sustain a good a 55mpg average at the end of the month though. I plan to start borrowing my wife's whenever I'm on the highway, I think this way I can average mpg in the 70s overall when I do this.
  - bananas 13y ago
    I get 58 solid. Prius is quoted at 50 here in the UK. If I'm on a flat road at 40-50mph (north circular) I can get a solid 80mpg average. Just have to stay easy on the throttle and not change speed.
- jbondeson 13y ago
  You do realize that you're comparing a diesel car to a standard petrol-hybrid right? Diesel engines are ~33% more efficient per-liter (and usually that much more expensive). The number for a Prius-hybrid you'd really care to look at would be the city driving numbers as that's where you get all the advantages of regenerative breaking. Running a Prius at 100+ km/h it just turns back into a standard petrol fueled vehicle carrying drained batteries.
  - bananas 13y ago
    Yes. It's about the end game, not the tools. I've found diesel engines and vehicles to be considerably more reliable and therefore less expensive. Fuel is between 5-7% more expensive here in the UK so things are good there. The city driving numbers are about the same I found. I regularly drive right into London's congestion charging zone - at least 1-2 times a week. 51 is the expected MPG in city driving scenarios. I can achieve that with no particular effort in London traffic. I don't drive like a crazy person and hang back regularly - that is all. My vehicle doesn't have piles of expensive electronics, batteries and things to go wrong either (look at recent threads about Toyota stack overflows for example). The most expensive thing on a Diesel that can go wrong is the particulate filter, EGR valves and timing chains and these are cheaply regenerated and replaced respectively.
tallanvor 13y ago
It pretty much has already happened. Most cars that offer both versions are very similar in terms of mileage for automatics and manuals - the difference is usually only like 1 or 2 mpg, with the automatics actually coming out on top at times because the car makers can add more gears. And realistically, most drivers aren't as good at using manual transmissions as they like to think they are, which also does a lot to cancel out the theoretical improvements a manual transmission offers.
bsder 13y ago
Not really, an automatic transmission always adds some amount of weight over a manual transmission. And this is why electrics are eventually going to win. A motor optimized for a single RPM speed driving a generator doesn't need a transmission. Even if the rest of the drive chain was as efficient, the loss of weight would drive the change over time.

josephlord 13y ago

A traditional automatic with a torque converter will always be less efficient I but the newer dual clutch models can probably match (or even exceed through better gear selection) the efficiency of manuals.

Marazan 13y ago

Without being able to determine future road conditions then automatics can't guarantee being in the "right" gear for the up coming section of road. Be that due to traffic, grading, weather, banking, sharpness of corner etc. My go to example is the insanity of junction 15 of the m8, that loop onto the west bound motorway is a 270 degree corkscrew rising 30 feet with a diameter of 55 yards onto a 5 lane motorway where I need to go from the left hand lane to the right hand lane (as there are entrance and exit lanes on both the inside and outside of the motorway at that point). A current automatic engine wouldn't know what was the right thing to do in that situation ( https://www.google.co.uk/maps/@55.8672951,-4.2358853,374m/data=!3m1!1e3 https://www.google.co.uk/maps/@55.8672951,-4.2358853,374m/da... ) To determine all of that you'd basically be at the level of self-driving car. Which would be awesome.

gambiting 13y ago
>> Without being able to determine future road conditions then automatics can't guarantee being in the "right" gear for the up coming section of road. Be that due to traffic, grading, weather, banking, sharpness of corner etc. Latest Rolls-Royce Wraith does exactly that - it uses the GPS map data to change gears in advance as it is approaching a turn in the road. I am sure that this technology will be available in ordinary cars soon enough.
- emidln 13y ago
  An augmented version of this technology (applying known map data plus sensor data) is a huge piece of the self-driving car.
dagw 13y ago
Your GPS already knows where you want to go, what the road ahead looks like and often even the current traffic situation. I imagine writing some semi-smart software that hooks up that info to the automatic gearbox to give it hints about what to do wouldn't be outside the realm of possibility and no doubt a lot easier than self-driving.
- gambiting 13y ago
  There are cars which already do exactly that: http://www.dvice.com/2013-3-7/new-rolls-royce-looks-ahead-gps-pick-right-gear http://www.dvice.com/2013-3-7/new-rolls-royce-looks-ahead-gp...
ecopoesis 13y ago
Or just buy a Nissan Versa today: http://www.edmunds.com/fuel-economy/five-myths-about-stick-shifts.html http://www.edmunds.com/fuel-economy/five-myths-about-stick-s... Manuals have better fuel usage then automatics is a myth for recent cars, no fancy self driving needed.
- Marazan 13y ago
  That's based on the official figures. No-one gets the listed MPG ratings in real life and automatics suffer worst than manuals for under-shooting the official mpg rating.
- sitharus 13y ago
  I just purchased a Toyota Yaris. The official figures for the 1.3L engine give 5.7L/100km for manual and 6.3L/100km for the automatic. Now in a high-end car with a sequential gearbox this is different, but for a small town car when you'll be doing a lot of starts and stops you'll see the losses on the hydraulic coupling.
mschaecher 13y ago
I have a feeling being able to determine immediate near term road conditions is a 1.0 feature for self-driving vehicles? Waze-style technology + GIS + networking with other vehicles + weather data (if you look, there is already tons of small weather monitoring stations all over major). thoroughfares). I mean many vehicles within the last handful of years have automatic traction control that can react faster to a real time change in road conditions than any human could ever hope too. A lot of the stuff I mentioned above is just extending that foresight out further so as to not be so jarring.
grmarcil 13y ago
I'm a die-hard manual fan, so you have my sympathy here. That said, I think current automatic technology is at the point where it can handle your go-to example with no problem. Yes the responsiveness of your base-level Toyota/Honda/Ford automatic transmission is going to be lacking versus a manual, but step up to a Mercedes or BMW double clutch automatic gearbox, or just go straight to the top of the automatic heap with Porsche's PDK transmission, and I think you will find all of them quite performant, even without paddle input. To preempt the "but you have to own a porsche for that!" responses, I'm not saying this is cheap, I'm just saying it is not limited by the available technology, just cost.

bananas 13y ago

You'd think so but I get 7mpg more than the best rated Toyota hybrid which is supposedly the most efficient thing out there. Bear in mind I drive a 6 year old 1.3L diesel Fiat van converted to a people carrier which is as aerodynamic as a shed. It also has 3 children, a buggy and a pile of crap in it. Perhaps a computer could optimise this better but I doubt it. The computer and automatic box just goes when you push the pedal down. The driver isn't connected to it and feeling what it's doing and understanding the power curves.

selmnoo 13y ago
> You'd think so but I get 7mpg more than the best rated Toyota hybrid which is supposedly the most efficient thing out there. You sure about that? Because I easily get about 70 mpg on my Prius (C class) when I'm supermiling in the city. Granted it's not as efficient on the highway, and unfortunately I do have to do a lot of highway travel. I can sustain a good a 55mpg average at the end of the month though. I plan to start borrowing my wife's whenever I'm on the highway, I think this way I can average mpg in the 70s overall when I do this.
- bananas 13y ago
  I get 58 solid. Prius is quoted at 50 here in the UK. If I'm on a flat road at 40-50mph (north circular) I can get a solid 80mpg average. Just have to stay easy on the throttle and not change speed.
jbondeson 13y ago
You do realize that you're comparing a diesel car to a standard petrol-hybrid right? Diesel engines are ~33% more efficient per-liter (and usually that much more expensive). The number for a Prius-hybrid you'd really care to look at would be the city driving numbers as that's where you get all the advantages of regenerative breaking. Running a Prius at 100+ km/h it just turns back into a standard petrol fueled vehicle carrying drained batteries.
- bananas 13y ago
  Yes. It's about the end game, not the tools. I've found diesel engines and vehicles to be considerably more reliable and therefore less expensive. Fuel is between 5-7% more expensive here in the UK so things are good there. The city driving numbers are about the same I found. I regularly drive right into London's congestion charging zone - at least 1-2 times a week. 51 is the expected MPG in city driving scenarios. I can achieve that with no particular effort in London traffic. I don't drive like a crazy person and hang back regularly - that is all. My vehicle doesn't have piles of expensive electronics, batteries and things to go wrong either (look at recent threads about Toyota stack overflows for example). The most expensive thing on a Diesel that can go wrong is the particulate filter, EGR valves and timing chains and these are cheaply regenerated and replaced respectively.

tallanvor 13y ago

It pretty much has already happened. Most cars that offer both versions are very similar in terms of mileage for automatics and manuals - the difference is usually only like 1 or 2 mpg, with the automatics actually coming out on top at times because the car makers can add more gears. And realistically, most drivers aren't as good at using manual transmissions as they like to think they are, which also does a lot to cancel out the theoretical improvements a manual transmission offers.

bsder 13y ago

Not really, an automatic transmission always adds some amount of weight over a manual transmission. And this is why electrics are eventually going to win. A motor optimized for a single RPM speed driving a generator doesn't need a transmission. Even if the rest of the drive chain was as efficient, the loss of weight would drive the change over time.