I currently drive a torque converter auto and as more and more cars going thru automated manual (dual clutch/pedal shift) mode, my choice for next car (not immediate though) with traditional auto is greatly diminishing.
So far I have driven only Toyota MMT and Honda iShift and both of them jerk/hesitate at low speeds, hills etc. I have also driven Merc C class (2009 model) which was far better but I can't recall if that one was DCT or TC.
Among all reasonably priced cars, which ones offer really good automated-manual transmission which is just as seamless as traditional torque converter autos (and reliable)?
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Don't forget the CVT's Sahib, I'm a 'TC man' too but, I would con-sider a a CVT, especially as the gnu Scooby doo Foz is only available with said box of gears.
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Not answering your question, but the new Mazda6 has a TC auto as an option - and yet still keeps emissions low. I assume they've done something different to keep emissions low so maybe not a traditional TC gearbox?
When I test drove my car as a DSG variant it seemed to work well enough. At roundabouts I didn't experience what some complain about - hesitancy before it moves off. But, when parking it up I found it wouldn't creep that well. I figured out later that was because of the auto-hold... so as I was touching the break when reverse parking an unfamiliar car I was engaging autohold (I think)... and then needed to push the accelerator to get moving again.... and then repeated it. If I'd turned off auto hold I think I'd have been fine :-)
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Would have thought any DSG (VW, Audi, Seat, Skoda etc) should do nicely.
Very impressed with the ones in my brother's CC and dad's Superb, though I'm not entirely sure whether the rev counter is fibbing when it snaps to the left during a gear change.
Nothing's broken yet and fuel economy excellent. Being diesels the gearbox is shuffling rapidly but you can't really tell. The Superb is remapped to 220 bhp and the gearbox doesn't seem bothered.
HJ hates them - presumably because one little old lady somewhere had a problem and wrote in to complain - but anecdotally, I've not heard of anything.
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There are 4 types of automatic box, really:
TC. That we all know and (some) love. Their only real problem is one of wasted energy in the converter, hence higher fuel consumption and emissions, which is why new-fangled stuff has been developed.
CVT. Pioneered by DAF. Constantly altering ratios and a constant whining to boot. Personally I find them the worst option.
Automated manual (single clutch). A robotised clutch and gear-change that can be jerky and unsatisfying for some. I think you need to not be in a hurry and not too fussy to get on with these. I've tried them in a Smart and Citroen (EGS) and personally don't like them. They are cheap and economical, though.
Automated manual (twin clutch) VW DSG, Ford Powershift, etc. A more expensive but better solution than a single clutch and the closest in driving feel to a TC. About as economical as a manual, if not more so. Yes, there is some delay and hesitancy, but so there is in any drivetrain, really (even letting a clutch in).
But as a lot is down to the individual, you really should try before you buy.
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>> Automated manual (single clutch). I've tried them in a Smart
I had one in a Smart Roadster, and once you've got the hang of leading the gearbox with throttle control rather then letting it lead you, it's a very satisfying and smooth thing to drive. You tell it to change by lifting off the throttle just a little at the right moment. If you just bury the pedal and let it change when it thinks it's right, you get jerky gear changes. Different to a TC auto, but really quite enjoyable when you get the feel, and that doesn't take long. I quite miss it and would have another one.
I've also had a DSG VW Touran, and I absolutely loved everything about that box, except the hesitancy on pulling away. There's just no way round that. And as I drive mostly in a congested town, I couldn't put up with it and binned it for a car with TC auto. I'm now back in a proper manual and getting a tired left peg.
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There's a fifth!
That's the thing that Toyota / Lexus describe as e-CVT in their hybrids, which isn't really a gearbox at all. Effectively a big differential with engine power applied at the planet carrier. The amount of power that goes to the annulus (drive) or sun gear (generator) is varied by the amount of torque or countertorque applied at the sun gear.
A second motor/generator on the annulus either applies drive directly for low speed use or scavenges power on the overrun.
Sounds complicated, actually fiendishly simple. The effect is the same as a CVT, only silent in operation and very smooth.
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Wonder why that wasn't used in the new Lexus LS hybrid which apparently drones on like all CVTs.
The Mazda6 TC is not a normal TC. I think it has some characteristics shared with a DSG.
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How the creeping is managed in automated manuals?
A torque converter uses fluid so creeping can be explained. But for an (automated) manual, at a slow speed engine should either stall or rev higher (which then won't be creeping but galloping).
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'''which ones offer really good automated-manual transmission which is just as seamless as traditional torque converter autos (and reliable)?'''
A very short list of none Movi.
To be fair the twin clutch jobbies are nice on the open road, but i haven't found one of them any automanual any use whatsoever for close manoeuvering or junction work where precise control is required.
Even Toyota are moving away from automanual, if they can't get it right (and they haven't) then i suspect its not going to happen for some time yet.
I won't be having one, the only reason my lorry is driveable in any real manner is because i override the auto function.
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>> Even Toyota are moving away from automanual
Moving to what?
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>> Moving to what?
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CVT (as in 09 on Avensis lovely box) and their smooth as smooth can be Hybrid drive.
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My experience with DSG was positive.
A friend has a Renault megane CC with their version of DSG. I found it remarkably smooth, although he does say it can get confused if you vary your speed i.e. accelerate, slow down, then accelerate again and has caught him a couple of times hunting around for which gear to choose
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I've had my DSG since new (6 years) and I love it, but don't forget that with the DSG's there are two different types. The older 6 speed ones have a wet clutch and can handle higher power outputs whereas the newer 7 speed ones use a dry clutch, maybe this has a bearing on the way they behave.
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I would caution that whatever kind of rubber band Citroen use is absolutely appalling, and if I never drive one again it'd be too soon.
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I agree with Boxsterboy above, who gave an excellent summary, with the proviso that the CVT that Audi use is very good. It doesn't have the "whining" that most CVTs seem to have, and the changes of gear ratio are smooth with no "hunting". It also creeps OK for parking, though not as well as a TC. The payoff is in fuel economy, which is very good for an automatic.
That said, like many others, I believe that nothing compares to the proper setup of torque converter + planetary gearset.
Someone mentioned the Mazda 6. Well the Mazda 3 is due out soon, and has been promised with an automatic gearbox. I strongly suspect that it will have the same gearbox as its bigger brother.
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My understanding of Audi's implementation of a CVT is they emulate gear ratios to avoid the whining sound. A reviewer of the Lexus LS said that they'd been in one where a software updated had improved it by also working like the Audi ones - and yet Lexus does not release the update.
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>> My understanding of Audi's implementation of a CVT is they emulate gear ratios to avoid
>> the whining sound.
That's about the size of it. In "Sport" mode they just have 8 fixed ratios and step between them exactly like a conventional automatic. You'd never know that it was a CVT.
You can use the standard flappy-paddles in any mode to select your own gears as well, which works just like a conventional automatic.
In "Normal" mode, when you accellerate in a traditional CVT the engine revs increase rapidly and the speed catches up gradually in a rubber-band effect. Many people find this very off-putting. In the Audi implementation, the revs go up more in steps, allowing the speed to catch up each time, then increasing again.
It feels normal to drive but just a bit too smooth to me. You still don't get the feedback that a DSG or TC box gives you. Still, I've no complaints with the efficency or performance. :-)
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Hve driven a couple of Twinc lutch autos, neither crept at all.
Creep is the drag of the torque converter and twin clutch are either engaged or not, would need more practice parking before I considerd owning one.
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>>CVT. Pioneered by DAF.
Are you sure?
IIRC Mobylette mopeds were around before.
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My scooter has CVT - yeah, that one ! - I get on quite well with that aspect, engine braking leaves a bit to be desired - I have bonded with it a bit now, but I wouldn't buy another (mainly small wheels thing).
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Mitsubishi Colt. Same as in the Evo. It's a damn good car and when you get used to an automated manual you have the best of both worlds. The only thing NOT to be recommended in our 59 plate Colt are the darn seats. No support and most uncomfortable except for short journeys, but the gearbox is a peach.
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>>but the gearbox is a peach
Juicy then?
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C.V.T. Was pioneered by Daf Van Doorne brothers in motor cars.
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My Jazz has 7 speed fixed CVT and TC.. Very smooth, no whirring ,,, some creep at stop - enough to make driving in jams very easy.
No confusion ever. S(port) mode great for pressing on. In D(rive) 70mph in 7th = 2200rpm.
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>> My Jazz has 7 speed fixed CVT and TC..
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How can it have both?? Are you sure it isn't a stepped CVT like the Audi discussed earlier?
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>> >> My Jazz has 7 speed fixed CVT and TC..
>> >>
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>> How can it have both?? Are you sure it isn't a stepped CVT like the
>> Audi discussed earlier?
I found one article that does say that it has CVT and TC, but the English translation doesn't make sense so I won't link it. I can't find any more info on it other than to say it is just a CVT.
I'm sure madf will enlighten us :)
Last edited by: corax on Sat 29 Jun 13 at 11:48
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"Leonardo da Vinci, in 1490, conceptualized a stepless continuously variable transmission.
Milton Reeves invented a variable speed transmission for saw milling in 1879, which he applied to his first car in 1896.
The first patent for a friction-based belt CVT for a car was filed in Europe by Daimler and Benz in 1886, and a US Patent for a toroidal CVT was granted in 1935".
Wiki.
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How do you downshift in a CVT? I guess it doesn't have the options of PRND321 like in normal TC autos.
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>> How do you downshift in a CVT? I guess it doesn't have the options of
>> PRND321 like in normal TC autos.
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Floppy paddle override on Jazz.. Used it twice? Worked very well...one paddle for up, one for down..
Great for geriatric boy racers...
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I believe the TC in Jazz CVT autos takes the place of the problematic starting clutch they used to fit. I imagine the TC locks up pretty soon once you are moving though.
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>> I believe the TC in Jazz CVT autos takes the place of the problematic starting
>> clutch they used to fit. I imagine the TC locks up pretty soon once you
>> are moving though.
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Yes.. the starting clutches on the original CVT used to fail after 50-70k miles. And the automated manual I Shift was, I understand, born from a union with Satan and a gearbox...
Locks up fairly quickly? Yes.
Very very smooth changes though.. imperceptible. No jolts , bumps or hesitations. Just like an American auto from the 1960s without as much slurring...(pity about the lack of a V8 - more power really needed)
Last edited by: madf on Sun 30 Jun 13 at 17:39
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Best automated manuals that compare with TC? - Dog
