I’ve not driven trucks for a while now but from what I remember any automatic didn’t move unless you pressed the accelerator, so you could sit…handbrake off, in gear and it wouldn’t move
Drove an automatic car for the first time ever last week…was surprised to find it starting to move whenever it’s in drive/reverse, so you need to sit with foot on brake or handbrake on in traffic/lights etc. I thought it was broken but apparently every auto car does that?!
Why do they work differently…just cos the idle speed?
Technical lesson for you
Most trucks are a manual box and clutch with air driven electronic auto shifter and de clutcher ( hence you still hear the clunk of the splitter )
Most cars a full CVT continuous variable transmission than is constantly engaged in drive unless park or neutral is selected
The manual box/ electronic /air shifter and clutch is much better to drive! Although it’s prob just because I’m not used to auto cars. Wonder what system high end sports cars with flappy paddles use. And why some trucks take longer to change than others
All torque converter autos apply what’s termed as creep through the trans at idle.While the situation with automated clutched manuals if left in gear at a halt is anyone’s guess but if it de clutched when the brake was applied and/or accelerator is released it would obviously have no engine braking capability.The usual correct driving practice when stationary in most cases should be handbrake on in neutral whether manual or auto.Anything else is just laziness.
Wonder what system high end sports cars with flappy paddles use.
They can use either torque converter or automated manual with a clutch or double clutch.Such as the ZF 8 speed auto in the Jags etc,or DSG automated manual used in the Audis for example.
Cars with torque converter or fluid flywheel auto transmissions (also called 'slush-box) transmissions all tended to creep when in drive or reverse, a useful feature for slow speed manoeuvres (e.g. traffic queues, parking, funeral processions).
Problems have occurred when usually elderly drivers who changed to auto after a lifetime of manuals press the accelerator instead of brake and crash into other cars, canals, shop fronts. To avoid this some recommend left foot braking autos when manoeuvring.
Another downside was slightly worse fuel consumption than manual boxes, so with road tax based on CO2 emissions from the unrealistic EU tests manufacturers changed to DSG automated manual systems (as used in trucks but proving less reliable in many car applications).
Buckstones:
Cars with torque converter or fluid flywheel auto transmissions (also called 'slush-box) transmissions all tended to creep when in drive or reverse,
Is the right answer.
Some of the flappy paddle things in current fashion are not torque converter (or CVT with torque converter), they can be automated manual boxes same junk as we have in the lorries, or twin clutch jobbies (next gen in lorries and about time too) where the next gear either side is already in place and clutched, these are much faster in changes but still have hesitancy and fine clutch balance issues for the aforesaid slow maneuvers, junctions, and general power take up.
The twin clutch boxes fitted to cars have a so so reliability and durability record, as bad as automated manuals, and the cost to put them right can easily see the car an economic write off, i have no doubt the new lorry boxes will be properly designed and tested
Trad torque converter boxes might be less fuel efficient due to transmission drag, but so long as you give the makers service recommendation a healthy ignoring if it includes the immortal words ‘no servicing required’ or the howler ‘sealed for life’…pause for peels of maniacal laughter , torque converter boxes have proved themselves to be remarkably reliable for long term, i’ve run older cars for most of my life and have had many such autos since my first mk3 Zodiac , never had a gearbox failure yet apart from on the banger track , wouldn’t give you a thankyou for an automated manual or twin clutch jobbie.
To each his own I guess. There are still plenty of truck drivers who think auto boxes are the work of the devil.
I too have been driving automatic cars for a long time; even towing with them, but my current ride, with it’s six speed powershift box is by far the best yet; you really have to pay attention to spot the gearshifts. Unlike the earlier type used in the Focus, this uses wet clutches and hydraulic actuation; the decision to change being made by the computer like in a truck. I also have the paddles, but in practice only use the downshift to force it down on the approach to a junction etc.
Oh! Yes it will ‘creep’ even on level ground, and for long waits, it is best to knock it into neutral.
Quote Carryfast …
‘‘The usual correct driving practice when stationary in most cases should be handbrake on in neutral whether manual or auto.Anything else is just laziness.’’ unquote
Then I must be of the most lazy brigade as I never used a handbrake on any auto I’ve owned and there’s been quite a few and there’s no need to knock them into neutral either, and the Passat I have now has the auto hold facility. Technology has come a long way since the days of the Allegro …
Buckstones:
Cars with torque converter or fluid flywheel auto transmissions (also called 'slush-box) transmissions all tended to creep when in drive or reverse,
Is the right answer.
Some of the flappy paddle things in current fashion are not torque converter (or CVT with torque converter), they can be automated manual boxes same junk as we have in the lorries, or twin clutch jobbies (next gen in lorries and about time too) where the next gear either side is already in place and clutched, these are much faster in changes but still have hesitancy and fine clutch balance issues for the aforesaid slow maneuvers, junctions, and general power take up.
The twin clutch boxes fitted to cars have a so so reliability and durability record, as bad as automated manuals, and the cost to put them right can easily see the car an economic write off, i have no doubt the new lorry boxes will be properly designed and tested
Trad torque converter boxes might be less fuel efficient due to transmission drag, but so long as you give the makers service recommendation a healthy ignoring if it includes the immortal words ‘no servicing required’ or the howler ‘sealed for life’…pause for peels of maniacal laughter , torque converter boxes have proved themselves to be remarkably reliable for long term, i’ve run older cars for most of my life and have had many such autos since my first mk3 Zodiac , never had a gearbox failure yet apart from on the banger track , wouldn’t give you a thankyou for an automated manual or twin clutch jobbie.
Juddian has it correct on all levels. ‘Sealed for life’ is just asking for problems and needs to be ignored, a fluid and filter change every 50K miles or so will see big mileage from a trad torque converter auto.
Ive got a twin clutch flappy paddle change in my Cayman but wouldnt want to run the car out of warranty, its going after 3 years as the mechatronic part of the gearbox can cost thousands to replace…
norb:
So juddian ,are you already given the next generation the thumbs up before driving them ■■? Are you getting soft in your old age
To be fair Norb, though i call Arsetronic from a lorry drivers point of view (and i make the distinction between lorry drivers and steering wheel attendees, or wheel operatives as a Daf mechanic i know calls them ) and i include Merc’s auto box in that, there is no arguing that they have proved to be reliable and durable in use, and sad to say they are here to stay because half the half wits behind the wheel can’t be trusted not to ■■■■■■■■ up clutches and rip the teeth of the gears if they are trusted with a gearbox.
Result being these things are here to stay, and none of the new buggers in transport management is in the least interested in pleasing a few stubborn old bleeders who would like to still be lorry drivers and want to continue controlling their vehicles, in fact they’d be just as happy if us old uns dropped dead.
They insist on dumbing the job down, deskilling every aspect of the job, we all know why its so they can hire and fire at a moments notice can stick any bod the ageny sends 'em in the drivers seat, prat nav programmed (now being included in the car test ) select D and follow the instructions, simple eh?
I just wish more of us in the industry could see that the easier and dumber our jobs become, the less skilled mucky or involving of a bit of graft the less we are worth and the easier we are to replace, any bloody fool can select D and travel down a motorway on the limiter and that suits the suits.
So, thanks for allowing me a small, by my standards rant (don’t suppose any bugger’s listening or agrees ), but seeing as these poxy gearboxes are here to stay, i’ll welcome any advances that speed up the gearchanges back to the rate of the 70’s and 80’s, at least they won’t be quite so frustrating as the current offerings, chances of my gaffer ordering me a manual box with a proper lorry and suitable engine attached is a big fat nil.
Yer never know Merc might even come up with a way of getting the bloody thing out of gear if the air pressure drops
Snap Goldfinger, got 20 litres of Dexron 6 in the garage ready to go in my latest aquisition’s autobox when i change the oil, hopefully get the time this month, and 20 litres gear oil for the diffs and transfer box
Putting a torque converter box in to neutral at lights or in traffic just causes more wear when engaging clutches and bands. The fluid in the converter is doing the work. I’ve driven almost nothing but converter auto’s in cars since coming to Oz and find them to be more reliable and less trouble than manuals, I’ve never driven an auto truck. There seems to be an aversion in the UK to auto’s in cars, because of all the black magic involved, but I’ve stripped down and rebuilt a few for other people and they are just another piece of mechanical bits.