Once again I'm contemplating changing my car! I go through this process far too often of spending hours trawling Autotrader and then end up sticking with the Saab. More often than not, SWMBO reins me in.
I quite like the idea of going automatic, but other than one or two hire cars, I don't really have much experience of them.
Is there anything I should be looking out for when buying that I wouldn't with a manual apart from the mpg issue?
(For the record, I've seen an Astra 1.8 vvt auto and a C-Max 2.0 auto. Ok, as a curve ball, I've also seen a Volvo S60 manual 2.0 which I quite like for some reason too. Thoughts on any of these much appreciated!)
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With any auto it's servicing the oil is the key it has to be changed it can smell burnt due to high miles and will not change up feel sluggish etc, look for oil leaks, check fluid level.
If one packs in there is a torque converter these are expensive enough never mind the cost to overhaul the auto box.
So if you want one look for full service history and still ask the question what has been done to the auto box.
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The engine in the astra is not very refined and can be noisy.I have the same engine in my Vectra and i am not very pleased with it.Cannot comment on the autobox though.
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I think autos suit diesels better than petrols due to the narrower rev band. The one in my 335d is very good - not perfect, but given that the tail can break free if you try and put the power down too soon, it's nice to be able to keep both hands on the wheel.
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I think autos suit diesels better than petrols due to the narrower rev band.
That's an interesting viewpoint. I thought a petrol was better for auto because the box would change down when more power was required, which works better for petrol engines.
Does a diesel auto work OK when you hoof it, or does it end up making a lot of noise for little gain?
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With any auto it's servicing the oil is the key it has to be changed.....
Well, the 5-speed Aisin-Warner 'box in my S80 is supposedly 'sealed-for-life'.
The same fluid's been in there since 1999, and - 160k miles later - the 'box still shifts flawlessly :-)
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The merc auto's are also sealed for life but on there forums all they talk about is problems a dipstick is needed does not come as standard & plenty of info and photo's dropping the oil.
At 160k your doing exeptional top class cars thought a merc would be in the same league.
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Mmm, well, you might not want to hear this but the Saab 9-5 2002-on model has a very good auto box, 5-speed and lockup in 5th over (I think) 55mph - effectively this means that on the motorway the economy is similar to a manual. I have a 2004MY Aero estate auto, and I get 33mpg on a run cruising at around 90mph (most of out motorway driving is in Germany :-) although it's about the same at 75mph. Admittedly it's worse around town, although we don't do any real town work but crawling through traffic drops it to around 25-26. Also on the plus side, 9-5s have never had great manual boxes (changes can be a bit notchy and slow). The oil change interval for the Saab is 90,000 although I found a great improvemnt when I had it done at 75,000 with a triple change - uses 10 litres of oil but you change 87% of the fluid. Most people seem to think that the Aero is better as an auto, and around 90% of them are autos. I wouldn't go back to a manual 9-5.
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Surely Mike H, if your doing mostly motorway driving it doesn't matter whether its a manual or an auto box really.
And what's with these 'triple fluid changes' - is that to flush the system out thoroughly?
Don't get me wrong though, I'm a 'dyed in the wool' auto man & have been for decades now, I can drive a manual but then again I can start an engine 'on the handle' :)
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> I can drive a manual but then again I can start an engine 'on the handle' :) <
Yup - says it all really.
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The 335d auto will drop either one or two gears depending on how quick you press the loud pedal. When it drops one gear it pulls quickly - when it drops two you know about it.
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Oh ere
theres ones on ere as is even older ( apparently) than I am
shocked I am
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Diesel auto is superb. Due to the torque of a diesel they are well matched.
When my landy drops into 6th on a motorway is doing about 1600rpm @70mph, makes fantastic cruising & good econometric
So much quicker out of side turnings & away at traffic lights manual is just plain hard work.
My auto also changes down gear on its own down hill so no need to sit on the brakes approaching junctions & down hill descents. They are so much better now. You can have a sport mode or drive it like a manual, but really no need.
Auto now for me any day.
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Actually actually back in the bad old days
when automatics were only 3 speed ( and some were only 2?)
one generally needed a torquey petrol to work with the lack of gears
compensating with the spread of revs
Diesels however could not deliver the spread of revs
Now with multi speed automatics, 6,7 8 even?
Diesels rule
as they can work within a restricted rev range / sweet spot
Or is the above gibberish
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You can have a sport mode or drive it like a manual, but really no need. <<
For 5-6 gear torque-converter autos, and dual clutch autos (DSG-style) nowadays this really is true - the electronic control gubbins is invariably better at selecting gear than the driver unless you're being a hooligan.
For single clutch automated manuals, however, manual (clutchless) gear changes are usually smoothest.
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Actually actually back in the bad old days
when automatics were only 3 speed ( and some were only 2?)
* Just out of interest, does anyone know how many gears the 2.0 petrol C-Max auto box has?
(Oh, and as ever, thanks all very, very much for the brilliant responses)
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Surely Mike H if your doing mostly motorway driving it doesn't matter whether its a manual or an auto box really.
Not quite what I actually said Perro - my point was that most of my MOTORWAY driving is in Germany, qualifying the 90mph comment! The rest is a mix, and included a 17 mile commute across country and through towns.
And what's with these 'triple fluid changes' - is that to flush the system out thoroughly?
Yes - a single drain and flus will only take out about 3 litres of the 5 or so that;s in box including the torque converter, the triple change simply takes out a greatre proportion of the old oil
Don't get me wrong though I'm a 'dyed in the wool' auto man
And I was a dyed in the wool manual man - but I like the auto.
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As for diesels and autos, there's a common misconception with diesels that revving the engines is pointless, it's not. This leads to the incorrect idea that autos won't work with diesels.
However, the old rule always holds true: torque x revs = power, specifically, torque in lb/ft x revs divided by 5252 = power in bhp. More revs, petrol or diesel, equals more power, until the point when the rapidly dropping torque of the engine cancels out the increase in revs. Even if peak torque is around 2k rpm, peak power will still be around 4k rpm.
So there's no reason why a diesel is any more, or less suited to an autobox, as long as there's enough ratios (as dieseldogg points out), so that when it goes up a gear in normal driving (say 2.5k rpm), it doesn't drop revs too low into the dreaded turbo lag zone below 1800 rpm or so.
For this, 5 speeds is usually enough for a diesel, more is even better, for any engine for that matter, and improves things yet further as you approach the infinite number of ratios of a CVT box where the engine can be cruising along at optimal economy or producing peak power at any road speed by simply changing gear.
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Oh this reminds me of the only 2-speed auto I've experienced.... Dad's 60s Vauxhall Victor 101 Estate.
Up our local Cotswold hills it would take off until it was screaming in first then drop into second whereby the 1600cc 60bhp engine would bog down and it would gradually slow until it changed down to scream away in first again. Hopeless.
Things may have changed massively.... but I still like a manual.
Edited by M.M on 19/11/2009 at 10:54
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Amazingly, 40 years on, and our Zafira isn't much better than this when fully loaded on steep, slow Cornish lanes. Screaming in first, then drops down to second and struggles to move. It uses the old 4 speed auto box, which is definitely not enough for a modern car IMO. 2 speeds must have been awful!
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Interestingly
our Steyr Puch Van with the Mercedes 4 speed auto, on a 3 litre diesel engine
Is faultless ( judged by my very limited experience)
Why
Because it appears to change gears at the same revs as i do manually in the TDI Galaxy
just an observation
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Must admit I'd always said I'd only think of an auto now if thinking of a lottery win car with big engine. Years ago we had loads of 3500 Rover autos and they burbled along OK with their 3-speeds... as did the 3.0 Granads and later 2.8s.
Another hopeless case was a 3-speed Viva HB from the late 60s. Had an 1147cc engine with apparently no power at all.... kept it just one month.
Thought the Zafira would have been better than you say though.
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The original late 70s Honda Prelude Coupe had a 2 speed automatic gearbox. Honda designed and built it themselves. goodness knows why, by then most automatics already had 3 speeds and the Mercedes and ZF transmissions had 4.
Edited by Webmaster on 20/11/2009 at 01:38
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I had a 1986 Prelude auto - 4 speed and really rather good compared to my 1980 Maxi 4-spd auto :-)
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