My campervan is a a diesel automatic Toyota Hiace.
I'm very pleased with the van, as a whole, and I really like both the torquey turbo-diesel engine and the smooth autobox. Much much nicer than wrestling with the heavy clutch and gearchange of most vans.
The only problem is that the engine and gearbox are a rather inefficient combination. If I try accelerating to overtake, the gearbox drops a gear, and engine revs go up from the 2,000 of normal 60mph cruising to over 3,000 ... which is well past maximum torque. The result is great sound and fury, but not so much extra acceleration.
It seems to me that the gearbox is programmed accordingly to a logic which would be perfect for a petrol engine, but is wrong for a turbo-diesel. AFAICS, the turbo-diesel should not drop a gear on kickdown -- it should the gear and use the torque.
I dunno if newer diesel automatics are more intelligently programmed, but I'd want a decent test drive before buying a car with that combination. I'm pretty sure that my van would be a lot faster and less thirsty with a manual box.
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A friend has a diesel automatic Mondeo Mk 3. It goes OK but sounds like a distressed cow when he accelerates hard.
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>. AFAICS, the turbo-diesel should not drop a gear on kickdown -- it should the gear and >>use the torque.
It wouldn't be kickdown then would it though? That's what kickdown is - you press or 'kick'
the accelerator to the floor & it forces a changedown. I would simply press the throttle, not floor it. My diesel auto is the same - unless I make a vigorous throttle movement or floor it, it stays in the same gear. It just may be that you don't have enough power to attempt the overtakes you are & are having (or feeling you have to) 'kickdown,.
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>. AFAICS the turbo-diesel should not drop a gear on kickdown -- it should the gear and >>use the torque. It wouldn't be kickdown then would it though? That's what kickdown is - you press or 'kick' the accelerator to the floor & it forces a changedown. I would simply press the throttle not floor it.
I guess I was wrong to use the word "kickdown", because I'm talking about what happens when I press the accelerator rather than flooring it. (I thought that kickdown referred to the gerabox changing down in response to increased accelerator pressure, not just to flooring it. Sorry if I used the term wrongly)
My diesel auto is the same - unless I make a vigorous throttle movement or floor it it stays in the same gear.
I wish mine did that, but it doesn't. Even with a very modest increase in throttle pressure, it changes down. Perfect behaviour for a petrol engine, but not so good for a diesel, (unless revs have dropped very low on overrun).
Edited by NowWheels on 15/09/2009 at 20:57
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I wish mine did that but it doesn't. Even with a very modest increase in throttle pressure it changes down.
I wonder if your downshift cable has been overadjusted NW...if i'm gentle with the pick up's throttle i can make it stay in high gear much longer down to 1500 rpm or so before downchange, as i said before in cruise it drops a cog at the slightest incline.
Our gearboxes are probably very similar.
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Our gearboxes are probably very similar.
Possibly, but my camper is a 1997 vehicle, and gearboxes may have moved on a bit in that time.
But I'll get somebody to check the downshift cable, and thanks for the tip -- I didn't know what to ask for, and had assumed that these things had long since fallen under the control of some sort of electronic gadget.
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Possibly but my camper is a 1997 vehicle and gearboxes may have moved on a bit in that time.
You may well be right and it might be electronic but Toyota seem to be very old fashioned in their working vehicles, and nothing wrong with that.
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Diesel Automatics are a subject very close to my heart. (Made more complicated by my desire for a medium sized hatchback with this combo). It is a pretty thin field, I'm afraid. The bad news is that if you really are set against the DSG-type automatic, then it does restrict the choice even more.
Be aware that the 2-litre Focus uses its own version of DSG,called "Powershift", and the 1.6 Focus has a CVT box (Which themselves generate heated debate as to their pro's and Con's). IIRC the Toyota Auris "Multimode" transmission is CVT as well.
The Citroen C4 Automatic is another which divides opinion. They call their system EGS, and is reported to be rather jerky in operation.
Fiat produce an automatic version of the Bravo ("Dualogic"). I believe that this is a "clutchless manual", which also gets a lot of stick in the Back Room.
Possibly the nicest diesel with a conventional automatic gearbox, is the BMW 1 series. The official figure is 52 mpg combined, and I think that BMW real-world figures get pretty close to the claimed ones. Trouble is, that it costs 20 grand new! Maybe you have that kind of budget, but most of us won't.
The Vauxhall Astra is shortly due to be replaced by a new model, and you will get some good run-out deals if you are interested.
Another car worth looking at is the Renault Megane.
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Beware the 17" wheels with the cee'd - firm ride - revised model may be better - will also cost additional 85 pounds a year road tax over 16" wheels (emissions go from 119 to 126 Co2 g/km)
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I had a Skoda Octavia 2.0 TDI PD 140bhp with DSG. On the whole an auto with diesel makes sense as the box keeps the engine at optimum revs. However I would suggest you take an extra long test drive in any DSG vehicle as I found the box to be fairly rough around town. In start stop traffic I found it couldn't decide which gear it should be in and would sometimes change down with a fair wallop, or mid-entrance to a roundabout flounder and leave you without power.
In the end I found myself changing into sport mode when approaching a roundabout, just to make sure the power was there if I needed it, then change back to normal auto after that.
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Interesting thread and one close to my heart.
I find proper torque converter autodiesels to be one of the nicest vehicles to drive in town/traffic especially and all roads in general.
Again, and this is getting serious i agree with NW (i'm going to get help..;), the Hilux is autodiesel and the box is a dream, very smooth changes not far off the gliding ability of my old MB.
But it does exactly as NW finds, the 3litre d4d is a good engine developing max torque at 1400rpm, so it breezes around like a good 'un.
But, on the open road it will change down far too easily to the next lower gear when for example climbing a slight motorway incline (especially with cruise engaged), it really could have done with a manual override facility to lock the thing in top when on the open road...i can't believe i've just suggested that really it means more to go wrong, and is against my religion..;)
DD, have you tried the Astra autodiesel, nice box and if coupled to the 1.9 (assuming you can find that combo) should be a perky enough motor, what the durability is like i have no idea.
Other than that it's mainly the Korean makers that see fit to provide what people want.
I'm a little disappointed that it's taken Toyota until now to put an auto box in their Diesel cars (at least for UK market), and thats only in the new Avensis so far (bet it'll go in the Lexus is though), but that box does feel good.
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You are going through just what I have spent the last few months looking into .
Without trying to tell you how to suck eggs
1-- you have a automatic gearbox with a torque converter( advantage they tend to be smoother but use more fuel and give out higher CO2)
2--- DSG (VW Skoda Seat ) or Power shift gearbox (Ford and Volvo) advantage more fuel efficient and less CO2) but quite a good gearbox
3--- Clutch less gearbox which are controlled by electronics ( disadvantage totally unreliable and jerky (advantage cheaper to buy and fuel consumption and CO2 better).Avoid at all costs
I looked at all the options and would have gone for a DSG but the vehicles that were available were just not in the right combination .
I ended up with a Toyota Verso 2-2 diesel automatic (Torque converter same gearbox as the Avensis) its early days yet and does not seem to have the torque of a manual diesel despite being the same engine maybe with a few miles under its bonnet will get better .
You will find it very hard to find automatics to test drive (VW probably your best bet )
I tried the Smax out and it was very good but it is a large car
Edited by cuthbert on 14/09/2009 at 21:28
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I ended up with a Toyota Verso 2-2 diesel automatic (Torque converter same gearbox as the Avensis)
A rare beast indeed CB, few enough Verso's let alone a autoD, i didn't know they were out yet.
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Took about 6 weeks to come in !! they came out about the beginning of August !!
The previous gearbox in the old Verso was an MMT it was a total disaster . I would not even had contemplated one of those
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2--- DSG (VW Skoda Seat ) or Power shift gearbox (Ford and Volvo) advantage more fuel efficient and less CO2) but quite a good gearbox 3--- Clutch less gearbox which are controlled by electronics ( disadvantage totally unreliable and jerky (advantage cheaper to buy and fuel consumption and CO2 better).Avoid at all costs
Isn't 2 a variation of 3 ?
I find these clutchless gearboxes (EGS with 1.6HDi) OK and not unreliable at all.
Gearchanges on the upshift are smooth if you remember to ease off the throttle in the same way you would changing gear in a coventional manual.
Only downside is no engine braking. I find it better to use the paddles and manually select the gear I want for a corner or roundabout.
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I would not want to disagree with you as you have owned the Citroen so have some experience on the gearbox !!
I did consider the C4 Picasso but looking on the Citroen owners website and the comments made about the gearbox put me off
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I'm surprised any of us buy cars if we read the owner's websites :)
As has been said on here (and many other places) not many people blog about how wonderful their cars are but plenty report the problems.
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Yes I know people only post when they have a complaint so you tend to get a unbalanced view !!
But after owners experience on the MMT gearbox which was a total disaster it made me very wary !!
To be honest the only way to get an opinion on these type of automatics are through owners review as automatics are not freely available to test drive
Electronic gearboxes are the future but some are better than others and some are horrendous
I believe the DSG has two clutches and one engages the odd gears and the other engages the even gears and works well
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Electronic gearboxes are the future but some are better than others and some are horrendous
The one area which I had forgotten about (I have only had to do it once in six months) is manoeuvering into tight spaces. You really do miss the torque converter creep then and it becomes a two footed effort.
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"...Other than that it's mainly the Korean makers that see fit to provide what people want...."
No, they are just behind in developing their own double-clutch transmission; however last week's news from Kia shows they're catching up -
"...The Sorento hybrid uses a new 1.6-litre diesel unit, which is fitted with twin turbochargers to help it produce 161bhp. The engine is mated to an electric motor and drives the front wheels via a new double-clutch transmission offering a choice of fully-automatic, or manual sequential gear changes..."
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