I have driven proper auto box cars before so I know what they are like on hill starts etc.
However, I was wondering what the cvt variants and esytronic variants are like.
I watched animations of these (you tube is good for this) and it would appear that the clutch has disengaged the drive at engine idle.
A full auto will have that inevitable creep forwards, hence most auto drivers sit with their foot on the brake pedal in traffic.
So how do cars with CVT autoboxes or easytronic gears fair on hill starts ?
The easytronic gearbox is a manual gearbox with an electric window motor (and mechanism) to control the clutch.
wouldn't they roll backwards the moment the footbrake / handbrake is released or are there sensors to stop the car rolling back.
It is probably a stupid question, but it is a genuine question.
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Some have built-in creep, some have Hill Hold, others you drive like a manual - i.e. use hand brake or be fleet of right foot so you don't roll back into the car behind.
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In my opinion, give cars fitted with DSG boxes and their ilk a wide berth. Fine for open road motoring but dogs in heavy traffic and on inclines with heavy traffic.
I'm basing my comments purely on what I have read and a friend's experience with his car fitted with a DSG system.
I'd rather have a really sophisticated automatic like those fitted to BMWs (just to quote one class manufacturer).
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hmm good point.
It does make me think how long these easytronic and cvt gearboxes last.
They have been out a few years now so Id imagine garages must be seeing a few now.
Most proper autoboxes last well into 200k miles before things like bands need changing / scrap the car time.
I have heard that lorries are mostly semi auto boxes now, so they must be reliable right ?
Are those electronic controlled clutches or are those hydraulic ?
Last edited by: diddy1234 on Tue 10 May 11 at 11:57
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Drove a Citroen C3 with a DSG-style box and to put it bluntly, it were crap.
It rolled back, slow speed man-oover-ing was impossible, and you'd try to boot it out of a junction only to sit there while the gearbox got over the surprise of being asked to do some work.
Avoid. Conventional slushbox in my BMW which has some good creep. Most gradients it'll hold position, really steep ones you need to be prompt going to the accelerator or use the handbrake conventionally.
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That wasn't DSG style then, AF. DSGs do creep. Sounds like it was a single clutch automated manual. Different beast, DSG is far superior in most ways.
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>> I have heard that lorries are mostly semi auto boxes now, so they must be reliable right ?
Our MAN lorries have automated manuals. No difference in reliability or economy, but the clutches last a bit longer.
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>> Our MAN lorries have automated manuals. No difference in reliability or economy, but the clutches
>> last a bit longer.
>>
Ditto my Volvo. The biggest difference I've noticed is the lack of pain in my left hip, previously an occupational hazard after a day chasing up and down the manual box.
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>> The biggest difference I've noticed is the lack of pain in my
>> left hip, previously an occupational hazard after a day chasing up and down the manual
>> box.
>>
That's why I only drive autos on the daily grind.
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>> I have heard that lorries are mostly semi auto boxes now, so they must be
>> reliable right ?
In most cases yes, they have proved very reliable, however the vast majority of them are on normal fairly easy work, i've found that making certain one's do serious work can lead to overheating of the box which then either shuts down or selects all sorts of wrong gears until you stop and let it cool and restart.
As for hill starts, they can cope but slowly, and if the going is tough it's as well to go manual override.
The thing i really loath about them is that when slowing for a slight uphill, then going under power again the system takes so long to respond, several seconds in some cases, that the truck stops and starts to roll back...you have to learn to accelerate long before you need the power.
As per HarleyM's post with his Volvo...IMO they have the best set up automated manual boxes in the business, reasonably fast changes into the correct gear every time, very seldom have i needed to override with one of those.
Zero's post below, i agree with every word.
Last edited by: gordonbennet on Tue 10 May 11 at 20:50
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>> In my opinion, give cars fitted with DSG boxes and their ilk a wide berth. I'm basing my comments purely on what I have read and a friend's experience with his car fitted with a DSG system.>>
So your "opinion" is of no value as it's not based on personal experience.
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A "proper auto box" the OP said. That's a very true statement in my book. I want my auto box to be slightly lazy, slurring its changes, with a well controlled gentle creep at idle, an almost complete inability to roll backwards when in drive, with a nice T handle twixt the front seats. Its allowed to have 4 speeds and lock up in 3rd and 4th. IN fact exactly like they used to be.
If I want to change gears, I don't need flappy paddles, I will by a car with a gearbox, clutch and gear lever.
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>> A "proper auto box" the OP said. That's a very true statement in my book.
>> I want my auto box to be slightly lazy, slurring its changes, with a well
>> controlled gentle creep at idle, an almost complete inability to roll backwards when in drive,
>> with a nice T handle twixt the front seats. Its allowed to have 4 speeds
>> and lock up in 3rd and 4th. IN fact exactly like they used to be.
>>
You forgot to add "the increased fuel consumption". That's whats driving the newer 'automatic' boxes.
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Current car has a CVT automatic with electronic parking brake. Hill starts are easy. When stopped, put the parking brake on. When ready to move off, put the gear lever into "Drive", and press the accellerator. The electronic brake is released automatically and the car does not slide back.
My previous car had a conventional torque converter/planetary gear setup, and it was just as good at hill starts. No slipping at all.
Last edited by: Londoner on Tue 10 May 11 at 13:28
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I fancy a shot of an easytronic or other traditional automated manual. Just to see how they go... I think i'll test pilot just about anything :-)
DSG not strictly relevant, different technology but...
DSG hill start with hill hold control:
1. With foot on footbrake, engage drive with the gear lever
2. Remove foot from brake - car is held stationary as if brakes are still applied
3. Accelerate
DSG hill start without hill hold control:
1. With handbrake engaged, engage drive
2. Ease off handbrake as you accelerate
OR
1. Without handbrake engaged only footbrake, engage drive
2. Hold footbrake against drive for ~1 second
3. Release footbrake then take over the creep with throttle.
DSG will creep on any gradient (unlike a traditional auto), increasing revs slightly as necessary. It takes up to ~1 sec from drive being engaged for it to engage enough torque to creep on a very steep hill (hence the holding footbrake for that time).
Alternatively don't disengage drive and it'll immediately creep on removing footbrake.
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[Quote]A full auto will have that inevitable creep forwards, hence most auto drivers sit with their foot on the brake pedal in traffic.[/Quote]
Depending on inclination, the gravitational force may just balance out creeping force. So you will do nothing and car will just remain static :-)
Of course, doing this for extended period may overheat the transmission fluid.
But it shows how torque converter auto is so simple - no hill start circus, no jerk on gear change, fewer things to go wrong and not uneconomical either.
Of course, it is no longer fashionable.
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I've had my DSG mated with a 2.0 diesel engine for over 4 years now, and in that time it's been a life saver in the heavy traffic I contend with, hill starts are carried out as described by Skoda above, DSG creep is minimal but then you are effectively engaging 1st on engine tick-over which with my diesel will easily propel you along in slow moving traffic.
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My wife had a Merc A class with a strange gearbox. No clutch but manual gears. Didn't break but then she didn't keep it long. Didn't get on with it. I tried using it for some of my business trips because she preferred my Mondeo estate. I didn't get on with it either. You could drive it a bit like a proper auto on hill starts. Wouldn't roll back anyway.
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Previous car with DSG box for 3 years; current car with so-called "proper" auto - no difference in driving technique in traffic, on hills, starting, etc.
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Have a ford galaxy with powershift. It has a hill start function. It detects you are on an incline. If you press firmly on the brake pedal and then let go the brakes will stay on for milliseconds (or a second?) giving time for the transmission to engage and move the car forward. Never has the car rolled back. Useful when i visit family in Huddersfield, full of hills etc etc
Have also come across this in a manual Mitsibushi asx.
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cars with autoboxes - hill start questions - Boxsterboy
