Motoring Discussion > Automatic vs Manual of the same car Miscellaneous
Thread Author: diddy1234 Replies: 16
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New Mon 18 Oct 10 10:28 
 Automatic vs Manual of the same car - diddy1234
Are there any Automatic cars that are more fuel efficient than the manual version of the same car (with the same engine) ?

What with CVT and the like, I would have thought gear ratios could be more closely related to the engines characteristics.

Feel free to correct me, but wasn't the original mini more fuel efficient in auto form ?
Last edited by: diddy1234 on Mon 18 Oct 10 at 10:28
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New Mon 18 Oct 10 10:31 
 Automatic vs Manual of the same car - rtj70
Depends if your question relates to torque converter autos, CVT, twin clutch (e.g. DSG) or robotised manual.

It is quite possible to find cars with CVT and DSG gearboxes that are more efficient than a manual. But unlikely with a torque converter.
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New Mon 18 Oct 10 10:39 
 Automatic vs Manual of the same car - Ian (Cape Town)
Maybe depends on the driving.
My astra was better on the day-to-day than the manual version, as my route included lots of stop-start traffic, lots of hills etc etc
On the open road it was a minor difference between manual and auto - manual won.
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New Mon 18 Oct 10 11:46 
 Automatic vs Manual of the same car - lancara
VW petrol dsg autos usually give a better mpg than manual, but it is reversed for the diesels
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New Mon 18 Oct 10 12:51 
 Automatic vs Manual of the same car - movilogo
I think fuel economy on MT cars depends more on driving style compared to AT cars.

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New Mon 18 Oct 10 13:10 
 Automatic vs Manual of the same car - Tigger
The landcruiser 120-series (the one which has just been replaced) is officially rated more economical as an auto than as a manual. I remember noticing that when I bought mine. I don't know if the same applies to the new one (the 150-series).

Great auto on the 120 as well. But then it should be, given that Toyota own Aisin Warner.
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New Mon 18 Oct 10 18:43 
 Automatic vs Manual of the same car - Perky Penguin
ISTR that some of the 7 speed Merc autos are better on fuel than their manual counterparts, with the same engine but I can't find the quote/figures. So many Mercs come with no manual option, after their years of making really dire manual boxes, that it can be hard to find any model on which to make a manual/auto comparison.
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New Mon 18 Oct 10 22:36 
 Automatic vs Manual of the same car - Londoner
PP, according to the Mercedes Benz website you are correct. :-)

The SLK 300 and SLK 350 are two examples where the official combined MPG of the automatic is a tad better than the manual.
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New Mon 18 Oct 10 22:51 
 Automatic vs Manual of the same car - rtj70
Even for Mercs with a manual option, the foot operated parking break put off a lot of purchasers.
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New Mon 18 Oct 10 22:59 
 Automatic vs Manual of the same car - diddy1234
I checked a few cars tech specs on parkers web site and the only one I could find was the automatic Fiesta (with 5 speed auto) that had lower emissions and better fuel economy compared to the manual version.
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New Wed 20 Oct 10 18:00 
 Automatic vs Manual of the same car - Lygonos
Forester 2.5 turbo 4-spd TC auto is a fraction of an MPG better than the 5-spd manual.

I'd imagine this is largely due to its longer top gear (27mph/1000 vs 23.5mph/1000).
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New Wed 20 Oct 10 20:27 
 Automatic vs Manual of the same car - Iffy
To generalise:

Years ago, the auto version was always a lot more juicy.

Now it seems to be more of a dead heat.
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New Wed 20 Oct 10 20:36 
 Automatic vs Manual of the same car - Collos
One other thing to remember is that with an automatic you do not have the same stress levels ,I drive a 5 series automatic and its wonderfull calming experience to drive my sons 330 manual is horrible I feel like going into a quite room after a day in it.
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New Wed 20 Oct 10 20:34 
 Automatic vs Manual of the same car - corax
>> Forester 2.5 turbo 4-spd TC auto is a fraction of an MPG better than the
>> 5-spd manual.
>>
>> I'd imagine this is largely due to its longer top gear (27mph/1000 vs 23.5mph/1000).

Well worth knowing considering Subaru's seem to get through clutches more rapidly than other makes.
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New Wed 20 Oct 10 20:47 
 Automatic vs Manual of the same car - Runfer D'Hills
Slushbox autos will always be less frugal than an identical car with a manual gearchange.

As for preferences, I'm like Jekyll and Hyde. I love an auto in heavy urban traffic or in a crawling jam. Everywhere else I prefer a manual.
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New Wed 20 Oct 10 20:50 
 Automatic vs Manual of the same car - Bagpuss
Generally speaking a torque converter automatic will normally be less economical than a manual as there is always slip through the torque converter (that's how they work) and the gearbox itself is a lot heavier.

The exception to this is at constant (higher) speed when the torque converter is bypassed by the lockout clutch and also on cars such as Mercedes with the 7G-Tronic which have a longer top gear than the manual equivalent.

CVTs don't have a torque converter and neither do the DSG double clutch type or the automated manuals. These gearboxes are also lighter than a torque converter automatic if not as light as a normal manual. The question then is whether normal driving with a computer deciding when to change gear results in better economy than the driver making the same decisions based on anticipation and forward planning which a computer can't do.
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New Thu 21 Oct 10 01:38 
 Automatic vs Manual of the same car - Londoner
>> The question then is whether normal driving with a
>> computer deciding when to change gear results in better economy than the driver making the
>> same decisions based on anticipation and forward planning which a computer can't do.
>>
Audi are tackling this issue with their more expensive cars, using the satnav to help the gearbox decide when to change up/down.

In any case, I'm pretty sure that an efficient automatic, whose paper figures are very close to its manual equivalent, will give better MPG for the average driver.

Another advantage of an auto is that it is difficult to thrash it. Very reassuring when you are buying second-hand.
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