Automatic better mileage than a manual?

[fleabag]

http://www.fueleconomy.gov/feg...c&hiddenField=Findacar

?

I'm very confused, why would the automatic civic get better mileage than the manual version? Does the EPA use poor shift points or something? I don't see how an automatic can get better than a manual.

 

[amdhunter]

Well the 6-sp version is the Si...so thats why that wastes more.
The similar 1.8's, I dunno.

I totally miss the gas mileage on my Civic. It was sooooo much better than my Jetta.

 

[3chordcharlie]

Gearing, powerloss, etc.

Traditionally, manual transmissions have had more ratios, and less powerloss than automatics. Final 'cruising' mpg should be pretty comparable with lockup torque converters.

Newer automatics have more ratios, and improved efficiency, plus smarter shift logic, and it is entirely possible for them to return equal or better fuel economy.

 

[overst33r]

Originally posted by: fleabag
http://www.fueleconomy.gov/feg...c&hiddenField=Findacar

?

I'm very confused, why would the automatic civic get better mileage than the manual version? Does the EPA use poor shift points or something? I don't see how an automatic can get better than a manual.

Probably due to taller gears in the AT.

 

[woodie1]

"Automatic better mileage than a manual? "

Gear ratios.

 

[fleabag]

Originally posted by: woodie1
"Automatic better mileage than a manual? "

Gear ratios.

So a lower top speed in the automatic? Or a higher top speed? You could argue either way how I see it..

 

[sniperruff]

automatics usually have less power and lower mpg... with the exception of a CVT transmission.

 

[3chordcharlie]

Originally posted by: sniperruff
automatics usually have less power and lower mpg... with the exception of a CVT transmission.

Which brings us to the OP.

 

[Pacfanweb]

Originally posted by: sniperruff
automatics usually have less power and lower mpg... with the exception of a CVT transmission.

Not these days. 6-speed autos, and the computer can shift it better and more efficiently than a person can shift a stick.

 

[fstime]

Yup, some automatics are better than others.


Thats why I find it funny when people apply the term "slushbox" to all automatic transmissions.

 

[The Boston Dangler]

Originally posted by: 3chordcharlie
Gearing, powerloss, etc.

Traditionally, manual transmissions have had more ratios, and less powerloss than automatics. Final 'cruising' mpg should be pretty comparable with lockup torque converters.

Newer automatics have more ratios, and improved efficiency, plus smarter shift logic, and it is entirely possible for them to return equal or better fuel economy.

:thumbsup:

 

[3chordcharlie]

Originally posted by: BouZouki
Yup, some automatics are better than others.


Thats why I find it funny when people apply the term "slushbox" to all automatic transmissions.

Uhh... do you know how a torque converter works?

Hint - at a really basic level, a fan 'turns' some slush, which 'turns' another fan.

 

[nakedfrog]

Originally posted by: woodie1
"Automatic better mileage than a manual? "

Gear ratios.

Makes sense that a manual would be geared for a sportier driving experience these days.

 

[jagec]

Originally posted by: BouZouki
Yup, some automatics are better than others.


Thats why I find it funny when people apply the term "slushbox" to all automatic transmissions.

They ARE slushboxes. Don't you know how they work?

Heavy, complex planetary gear system + torque converter (that's the most "slushy" part of it to me) + convoluted oil-pressure system to change gears...a lot of stuff is sloshing around in an automatic transmission, versus the simple direct linkage of a manual.

Modern technology has made them a lot lighter, a lot smarter, and a lot more efficient, but they're still a very overengineered solution which will always be more complex, heavier, and more prone to problems than an equally well designed manual.

 

[Colt45]

Torque converter = loss.


auto = 4.437 final drive, and 5th gear is .525, so 2.33:1 overall.
6spd = 4.765 final, 6th = .659, so 3.14 overall.
5spd = 4.294 final, 5th = .727, 3.12 overall.

So, say the auto runs 2500rpm @ 55MPH in top gear, the 6spd manual would run at 3370rpm, and the 5spd would be at 3350rpm.

Infact, this kind of proves the efficiency of the manual. The 5spd manual, at highway speeds, turns the engine 33% faster than the auto, yet only gets 2MPG less... and that is with the torque converter locked up.



The discrepancy between the 5spd and auto, is that the ratio favours the auto.
The 6spd is considerably poorer because it has roughly the same ratio as the 5spd manual, and 50hp over the other models.

 

[dug777]

Originally posted by: Pacfanweb

Originally posted by: sniperruff
automatics usually have less power and lower mpg... with the exception of a CVT transmission.

Not these days. 6-speed autos, and the computer can shift it better and more efficiently than a person can shift a stick.

Auto ratings are still generally lower than manual ones for the same vehicle, if not by much, from what I've seen...the other way round is still very much the exception, not the rule.

 

[Pacfanweb]

Ford Mustang 8 cyl, 4.6 L, Manual 5-spd, Regular
15 city/23 hwy
Estimated Annual Fuel Cost: $2,560

Ford Mustang 8 cyl, 4.6 L, Automatic 5-spd, Regular
15 city/22 hwy
Estimated Annual Fuel Cost: $2,560

Ranger

6-Cylinder Trucks

* 3L, 5-speed manual, 18 city / 23 highway

* 3L, 5-speed automatic, 17 city / 23 highway

* 4L, 5-speed manual, 17 city / 23 highway

* 4L, 5-speed automatic, 17 city / 23 highway

2006 Colorado

# 5 cyl, 3.5 L, 5-speed manual
19 city / 25 highway

# 5 cyl, 3.5 L, 4-speed automatic
19 city / 24 highway

Just a few examples I found in about a minute of Googling. Also found some that had a 2-3 mpg difference from stick to auto on certain models....which is an irrelevant number.
But an auto getting the same or nearly the same as a stick is NOT the exception that much anymore.

 

[fstime]

Originally posted by: jagec

Originally posted by: BouZouki
Yup, some automatics are better than others.


Thats why I find it funny when people apply the term "slushbox" to all automatic transmissions.

They ARE slushboxes. Don't you know how they work?

Heavy, complex planetary gear system + torque converter (that's the most "slushy" part of it to me) + convoluted oil-pressure system to change gears...a lot of stuff is sloshing around in an automatic transmission, versus the simple direct linkage of a manual.

Modern technology has made them a lot lighter, a lot smarter, and a lot more efficient, but they're still a very overengineered solution which will always be more complex, heavier, and more prone to problems than an equally well designed manual.

I was actually referring to DSG and SMG gearboxes.

I believe DSG setups have no torque converter.

 

[MixMasterTang]

Originally posted by: BouZouki

Originally posted by: jagec

Originally posted by: BouZouki
Yup, some automatics are better than others.


Thats why I find it funny when people apply the term "slushbox" to all automatic transmissions.

They ARE slushboxes. Don't you know how they work?

Heavy, complex planetary gear system + torque converter (that's the most "slushy" part of it to me) + convoluted oil-pressure system to change gears...a lot of stuff is sloshing around in an automatic transmission, versus the simple direct linkage of a manual.

Modern technology has made them a lot lighter, a lot smarter, and a lot more efficient, but they're still a very overengineered solution which will always be more complex, heavier, and more prone to problems than an equally well designed manual.

I was actually referring to DSG and SMG gearboxes.

I believe DSG setups have no torque converter.

Doesn't SMG stand for sequential manual gearbox (transmission)? And the DSG is defined as a The DSG is a development of the sequential manual transmission (SMT), which is essentially a fully-automated manual transmission with a computer-controlled clutch.

 

[Xyclone]

Originally posted by: BouZouki

Originally posted by: jagec

Originally posted by: BouZouki
Yup, some automatics are better than others.


Thats why I find it funny when people apply the term "slushbox" to all automatic transmissions.

They ARE slushboxes. Don't you know how they work?

Heavy, complex planetary gear system + torque converter (that's the most "slushy" part of it to me) + convoluted oil-pressure system to change gears...a lot of stuff is sloshing around in an automatic transmission, versus the simple direct linkage of a manual.

Modern technology has made them a lot lighter, a lot smarter, and a lot more efficient, but they're still a very overengineered solution which will always be more complex, heavier, and more prone to problems than an equally well designed manual.

I was actually referring to DSG and SMG gearboxes.

I believe DSG setups have no torque converter.

DSG's are twin-clutch (not torque converted) manual gearboxes. AFAIK, there are two gearboxes, one in control of gears 1, 3, and 5, and the other in control of 2, 4, and 6. In first gear you are using the first gearbox, while the second is getting the next (second) gear ready, and shifting takes place in .2 seconds i believe? Great transmission, expensive maintenance and questionable reliability (VW).

 

[fleabag]

Originally posted by: Xyclone

Originally posted by: BouZouki

Originally posted by: jagec

Originally posted by: BouZouki
Yup, some automatics are better than others.


Thats why I find it funny when people apply the term "slushbox" to all automatic transmissions.

They ARE slushboxes. Don't you know how they work?

Heavy, complex planetary gear system + torque converter (that's the most "slushy" part of it to me) + convoluted oil-pressure system to change gears...a lot of stuff is sloshing around in an automatic transmission, versus the simple direct linkage of a manual.

Modern technology has made them a lot lighter, a lot smarter, and a lot more efficient, but they're still a very overengineered solution which will always be more complex, heavier, and more prone to problems than an equally well designed manual.

I was actually referring to DSG and SMG gearboxes.

I believe DSG setups have no torque converter.

DSG's are twin-clutch (not torque converted) manual gearboxes. AFAIK, there are two gearboxes, one in control of gears 1, 3, and 5, and the other in control of 2, 4, and 6. In first gear you are using the first gearbox, while the second is getting the next (second) gear ready, and shifting takes place in .2 seconds i believe? Great transmission, expensive maintenance and questionable reliability (VW).

So with a triple clutch, more clutches control fewer gears, allowing for better shifting opposed to a single clutch that controls all of the gears?

 

[PlasmaBomb]

Triple clutches are single clutches with three friction plates not three clutches.

Single Clutch:http://i113.photobucket.com/al...ED_99/Singleclutch.jpg
Triple Clutch:http://i113.photobucket.com/al...ED_99/Tripleclutch.jpg
DSG diagram:http://i113.photobucket.com/al.../vw_dsg_diagram_lg.jpg
DSG cutaway:http://i113.photobucket.com/al.../vw_dsg_cutaway_lg.jpg
DSG theoretical model:http://i113.photobucket.com/al...heoreticalmodel_lg.jpg

Edit: For picture goodness

 

[dwcal]

Check the difference between the IS250 manual and auto. Auto 24MPG combined, manual 21MPG combined. I think the auto has taller gears. Slushboxes used to be heavier than manuals, but according to spec sheet, IS250 manual is 20 lbs heavier than auto.

 

[dug777]

Originally posted by: Pacfanweb

Ford Mustang 8 cyl, 4.6 L, Manual 5-spd, Regular
15 city/23 hwy
Estimated Annual Fuel Cost: $2,560

Ford Mustang 8 cyl, 4.6 L, Automatic 5-spd, Regular
15 city/22 hwy
Estimated Annual Fuel Cost: $2,560

Ranger

6-Cylinder Trucks

* 3L, 5-speed manual, 18 city / 23 highway

* 3L, 5-speed automatic, 17 city / 23 highway

* 4L, 5-speed manual, 17 city / 23 highway

* 4L, 5-speed automatic, 17 city / 23 highway

2006 Colorado

# 5 cyl, 3.5 L, 5-speed manual
19 city / 25 highway

# 5 cyl, 3.5 L, 4-speed automatic
19 city / 24 highway

Just a few examples I found in about a minute of Googling. Also found some that had a 2-3 mpg difference from stick to auto on certain models....which is an irrelevant number.
But an auto getting the same or nearly the same as a stick is NOT the exception that much anymore.

Which isn't quite what you originally said, or what I said