# DSG - Shifting into neutral whenever stopped?



## -PTK- (Jan 6, 2009)

I was reading the wikipedia article about DSG and saw that it mentioned always shifting into neutral when stopped. (http://en.wikipedia.org/wiki/D...2N.22 ) Is this for real? I never did this and never thought to, should I be? I don't see any citations for this part so I'm not sure where it's coming from. I might change it if I can determine it is not true. What do you guys think? 


_Modified by -PTK- at 8:04 AM 5-14-2009_


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## MisterJJ (Jul 28, 2005)

*Re: DSG - Shifting into neutral whenever stopped? (-PTK-)*


_Quote, originally posted by *-PTK-* »_I was reading the wikipedia article about DSG and saw that it mentioned always shifting into neutral when stopped. (http://en.wikipedia.org/wiki/D...2N.22 ) Is this for real? I never did this and never thought to, should I be? I don't see any citations for this part so I'm not sure where it's coming from. I might change it if I can determine it is not true. What do you guys think? 

_Modified by -PTK- at 8:04 AM 5-14-2009_

Sounds like someone talking out of their lower orifice.


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## mike3141 (Feb 16, 1999)

*Re: DSG - Shifting into neutral whenever stopped? (-PTK-)*

It's standard practice in the U.K. to shift out of gear while stopped at traffic lights. Don't know why they do it but it's apparently what they teach you to do over there.


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## fs454 (May 13, 2008)

I do this. I really wish there was a way we could flash the DSGs into shifting out of gear and into neutral while stopped instead of doing the "automatic creep." 
unpossible?


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## LWNY (Jul 30, 2008)

*Re: DSG - Shifting into neutral whenever stopped? (-PTK-)*

I don't think it applies to DSG since the clutch pack are effectively dual sided, there is not tensioned and untensioned position like on a regular clutch. So when fully stopped and the car in Drive, the clutch is not forced open against the tension of the spring, but sit in its neutral position.
As far as then gears being engaged, it should not matter since the car is not moving and it is just sitting in that gear, not turning.
As long as you have your foot on the brake and not letting the vehicle slowly creep, then nothing should be stressed.
The only possibility is that the pump is pressurized when in Drive so as to be ready to engage the clutch on moment's notice.


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## VWAddict (Jun 12, 1999)

*Re: DSG - Shifting into neutral whenever stopped? (mike3141)*


_Quote, originally posted by *mike3141* »_...Don't know why they do it...

Because sitting with your foot on the clutch and the engine running wears the throw-out bearing.

_Quote, originally posted by *MisterJJ* »_Sounds like someone talking out of their lower orifice. 

Nope.

_Quote, originally posted by *fs454* »_I do this. I really wish there was a way we could flash the DSGs into shifting out of gear and into neutral while stopped instead of doing the "automatic creep." 

Then when you took your foot off the brake, there'd be no engagement -not even partial- and you'd roll backwards on slight inclines. -In traffic-light queues, that'd be a real No-no, don't you think!

_Quote, originally posted by *LWNY* »_As far as then gears being engaged, it should not matter since the car is not moving and it is just sitting in that gear, not turning.
As long as you have your foot on the brake and not letting the vehicle slowly creep, then nothing should be stressed.


Wow! -That's WAY wrong. The gears are indeed not turning, -that part is correct, but the friction at the clutch is indeed causing wear/aging at the clutch-pack surfaces.
Keith


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## LWNY (Jul 30, 2008)

*Re: DSG - Shifting into neutral whenever stopped? (VWAddict)*


_Quote, originally posted by *VWAddict* »_
Because sitting with your foot on the clutch and the engine running wears the throw-out bearing.
Wow! -That's WAY wrong. The gears are indeed not turning, -that part is correct, but the friction at the clutch is indeed causing wear/aging at the clutch-pack surfaces.
Keith
You are under the assumption that the DSG is a single clutch transmission with a clutch plate that is spring pressurized. Keeping the clutch open in a single clutch system puts pressure on various components. But in a twin clutch system, the clutch plate is in a neutral, non-tensioned position. Pressure onto either side of the clutch is activate via hydraulic pressure. If they used springs like a conventional single clutch transmission, it would have a unstressed position of engaging on one side of the clutch plate, with your car effectively being stressed 50% of the during the lifetime it is being driven. Nobody would create such a design.
As far as the wear on the clutch pack surface, there is no engagement of the surface, since the clutch are disengaged when you have your foot on the brake.
If the clutch are constantly partially engaged, then you would feel a gradual creep when you progressively let off on the brake, but that is not the case. There is a certain point when letting off the brake in which the transmission decides that it should start engaging, that is why you notice a sudden creep instead of the fight against the brakes creep of a auto trannie.


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## AlaskaDG (Mar 12, 2008)

*Re: DSG - Shifting into neutral whenever stopped? (LWNY)*

The problem with shifting the DSG into neutral at a stop is that it takes a second or so to re-engage into drive, especially when you are on an incline. If you leave the DSG in gear, the car immediately moves when you hit the gas pedal.


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## VWAddict (Jun 12, 1999)

*Re: DSG - Shifting into neutral whenever stopped? (LWNY)*


_Quote, originally posted by *LWNY* »_You are under the assumption that the DSG is a single clutch transmission with a clutch plate that is spring pressurized. 

Not at all... Though I see why you might think that.
I was responding to the comment about why the British are taught (quite correctly by the way) to put a 'normal' manual transmission into neutral and let off the clutch if the car is going to be idling for any length of time, rather than staying in gear with the clutch pushed down.
That was the only reason why I mentioned the throw-out bearing, -I know that the DSG uses clutch-packs which operate differently, and I wasn't referring to DSG with that response, only to the quote which I'd referenced immediately above.

_Quote, originally posted by *LWNY* »_As far as the wear on the clutch pack surface, there is no engagement of the surface, since the clutch are disengaged when you have your foot on the brake.

This is not strictly correct. With my DSG transmission, when your foot is on the brake and the vehicle is stopped, the clutch is PARTIALLY engaged. That's how the car can 'creep' against light brake pedal pressure. If you want to demonstrate/prove that the clutch 'engages' slightly, stop the car, hold the brake pedal down lightly, put the car into neutral, and then alternate the shifter position between neutral and 'D', then back to Neutral, back to 'D'... every couple of seconds. -You'll feel the car 'tug' slightly when you go into 'D'.
Since both clutches are completely disengaged in 'N', if they were also completely disengaged in 'D', there would be no 'tug'.... But there is... and the car can even creep forward with the brake pedal slightly depressed. The brake pedal switch activates the shifter gate solenoid, so you KNOW that the car knows that the brake is operated.

_Quote, originally posted by *LWNY* »_there is no engagement of the surface, since the clutch are disengaged when you have your foot on the brake.

Perform the above demonstration/example. -You should see that there is indeed PARTIAL engagement; -obviously not full engagement, or the engine would stall!
Keith


_Modified by VWAddict at 5:18 PM 5/14/2009_


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## tdotA3mike (Feb 5, 2009)

*FV-QR*

i tend to do this mainly cause i have the stupid idea i might be saving fuel some how...







then i proceed to peel out at the lights.... lol


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## VWAddict (Jun 12, 1999)

*Re: FV-QR (tdotA3mike)*

You might be saving _perhaps_ a thimbleful per tank...
..But then you waste a cup with each and every peel-out!








Keith


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## tdotA3mike (Feb 5, 2009)

*Re: FV-QR (VWAddict)*


_Quote, originally posted by *VWAddict* »_You might be saving _perhaps_ a thimbleful per tank...
..But then you waste a cup with each and every peel-out!








Keith

ohh yeah! a tire killer too... lol like i said stupid... also doesn't help that i have HPA stage II with LC!. going to neutral, it makes me feel like i almost have a manual as well lol... i miss driving manual sometimes, at least the DSG is the next best thing..


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## LWNY (Jul 30, 2008)

*Re: DSG - Shifting into neutral whenever stopped? (VWAddict)*


_Quote, originally posted by *VWAddict* »_
This is not strictly correct. With my DSG transmission, when your foot is on the brake and the vehicle is stopped, the clutch is PARTIALLY engaged. That's how the car can 'creep' against light brake pedal pressure. If you want to demonstrate/prove that the clutch 'engages' slightly, stop the car, hold the brake pedal down lightly, put the car into neutral, and then alternate the shifter position between neutral and 'D', then back to Neutral, back to 'D'... every couple of seconds. -You'll feel the car 'tug' slightly when you go into 'D'.
Since both clutches are completely disengaged in 'N', if they were also completely disengaged in 'D', there would be no 'tug'.... But there is... and the car can even creep forward with the brake pedal slightly depressed. The brake pedal switch activates the shifter gate solenoid, so you KNOW that the car knows that the brake is operated.
Perform the above demonstration/example. -You should see that there is indeed PARTIAL engagement; -obviously not full engagement, or the engine would stall!
Keith
_Modified by VWAddict at 5:18 PM 5/14/2009_
The only way to shift from N to D is to have the brakes pressed quite firmly, so it is impossible to confirm. What I can tell you is that when in D, and I let the brakes go very gradually, you don't feel the brakes breaking away from the tug of the transmission like a slushbox would do. What you do feel is there is some point where the car would suddenly start tugging. I think that is the point where the car thinks it could start engaging the clutch. Same as in when I let go the brakes very suddenly, there is initially no creep forward, but a fraction of a second later, you would feel a sudden slight tug, indicating the clutch slightly engaging to simulate the creep of a slushbox.


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## VWAddict (Jun 12, 1999)

*Re: DSG - Shifting into neutral whenever stopped? (LWNY)*


_Quote, originally posted by *LWNY* »_The only way to shift from N to D is to have the brakes pressed quite firmly, so it is impossible to confirm.

Absolutely not the case. -In my car, you hear the solenoid 'clunk' as soon as you touch the brake pedal. The shifter will go with the brakes lightly pressed, and the car will creep forward.
With NO change in brake pressure or pedal position, you can alternately shift every couple of seconds: N -stationary / D -creep / N -stationary / D -creep / N -stationary / D -creep / and so on. This is asbolutely contrary to your statement, and I don't know if you've tried it or not, but if you like, I can video it.

_Quote, originally posted by *LWNY* »_What I can tell you is that when in D, and I let the brakes go very gradually, you don't feel the brakes breaking away from the tug of the transmission like a slushbox would do.
 There's only a partial clutch engagement, and I know exactly what you mean.

_Quote, originally posted by *LWNY* »_What you do feel is there is some point where the car would suddenly start tugging. I think that is the point where the car thinks it could start engaging the clutch. 

In fact the processor which controls the clutches looks at wheelspeed, brake switch, throttle position, current engine speed etc. and FURTHER engages the clutch. This is absolutely NOT the initial partial engagement. -You can prove it for yourself.

_Quote, originally posted by *LWNY* »_Same as in when I let go the brakes very suddenly, there is initially no creep forward, but a fraction of a second later, you would feel a sudden slight tug, indicating the clutch slightly engaging to simulate the creep of a slushbox.

Yes, I know what you mean, but the clutch pack is indeed lightly engaged. You're nticing the FURHTER engagement.
You want a demonstration of the varying degrees of engagement? release the foot brake (legally called the 'Service brake' in Britain... bit of trivia) but leave the HANDBRAKE on; or try to slow the 'creep' with the handbrake. -You'll feel the clutch engagement 'tighten up' without the engine altering speed significantly... there are several degrees of engagement, and the governing processor makes decisions based on the input conditions.
I know it's counterintuitive, but I can absolutely confirm that the clutch pack IS partially egaged when in 'D' and stationary with the service brake depressed... no matter HOW forcibly the pedal is held down.
Keith


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## MisterJJ (Jul 28, 2005)

*Re: DSG - Shifting into neutral whenever stopped? (LWNY)*


_Quote, originally posted by *LWNY* »_The only way to shift from N to D is to have the brakes pressed quite firmly, so it is impossible to confirm.

No, I think it is possible that there is some very slight engagement of the clutch. If you switch between N and D with your foot on the brake you can feel a VERY slight bump. Also, if you look at the tach while doing this you will see a very slight bump in the needle. I suspect that the hydraulic system powers up when you put it in drive and creates a very slight drag on the drivetrain. Whether this is due to some slight clutch engagement or just drag from the hydraulic system, I do not know. It may make sense to shift it into N or P if you are stuck in traffic and it doesn't look like you will be moving anytime soon but at every stoplight? No effin way.
I'm 1000% sure that it is not intended to be shifted into N at every stoplight. If that was the case it would be made quite clear in the manual and they wouldn't sell half as many cars if that was required.


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## LWNY (Jul 30, 2008)

*Re: DSG - Shifting into neutral whenever stopped? (VWAddict)*


_Quote, originally posted by *VWAddict* »_
Absolutely not the case. -In my car, you hear the solenoid 'clunk' as soon as you touch the brake pedal. The shifter will go with the brakes lightly pressed, and the car will creep forward.
With NO change in brake pressure or pedal position, you can alternately shift every couple of seconds: N -stationary / D -creep / N -stationary / D -creep / N -stationary / D -creep / and so on. This is asbolutely contrary to your statement, and I don't know if you've tried it or not, but if you like, I can video it.
Then your car must work differently than mine. I have to fully press down on the brake. The only sound I heard is some clunking, which I assume is the gears engaging/disengaging.

_Quote, originally posted by *VWAddict* »_ There's only a partial clutch engagement, and I know exactly what you mean.
If there is a partial engagement, then you would feel a tug, however slight, but it is not the case.

_Quote, originally posted by *VWAddict* »_You want a demonstration of the varying degrees of engagement? release the foot brake (legally called the 'Service brake' in Britain... bit of trivia) but leave the HANDBRAKE on; or try to slow the 'creep' with the handbrake. -You'll feel the clutch engagement 'tighten up' without the engine altering speed significantly... there are several degrees of engagement, and the governing processor makes decisions based on the input conditions.
You are not disproving my point, which is when the foot brake is fully engaged, the clutch pack fully releases.

_Quote, originally posted by *VWAddict* »_I know it's counterintuitive, but I can absolutely confirm that the clutch pack IS partially egaged when in 'D' and stationary with the service brake depressed... no matter HOW forcibly the pedal is held down.
Keith
Then how could Audi claim the the clutch would last the life of the car if it would be always engaged?


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## VWAddict (Jun 12, 1999)

*Re: DSG - Shifting into neutral whenever stopped? (LWNY)*


_Quote, originally posted by *LWNY* »_Then your car must work differently than mine. I have to fully press down on the brake. The only sound I heard is some clunking, which I assume is the gears engaging/disengaging.
If there is a partial engagement, then you would feel a tug, however slight, but it is not the case.

There is a partial engagement. COMPARE the vehicle's release on slight inclines between neutral and drive. -I can appreciate that you're not seeing it, but declaring that there is no diffrence is quite incorrect.

_Quote, originally posted by *LWNY* »_You are not disproving my point, which is when the foot brake is fully engaged, the clutch pack fully releases.

The only control input which I've seen from the brake system to the governing DSG processor is from the pedal switch. -That being the case it's impossible for the processor to know how hard the brakes are being stomped on; only that they're not fully released.

_Quote, originally posted by *LWNY* »_Then how could Audi claim the the clutch would last the life of the car if it would be always engaged?

It ISN'T always engaged, neither fully (of course!) nor patially. Firstly in Neutral BOTH afe fully disconnected, which means no wear. When fully engaged there is also no wear, and when in 2nd, 4th and 6th it is of course fully disengaged.
An addition, (and as an enlightening diversion) watch the behaviour in 'D' when you ALMOST stop. the car NEVER goes down all the way into first unless you come to an absolute stop. -If you slow way down to 0.5MPH and move off again, the car never goes below 2nd gear, but instead 'slips' the clutch in 2nd (another partial engagement) thus sparing the 'odd-numbered gear' clutch. -It does this to share the load and thereby extend the life.
We plainly disagree over this, but I don't know what to tell you. The clitch pack IS lightly engaged at all times while 'D' is selected, with the vehicle stationary and the service brake depressed. -It's just a fact. The engagement is so slight that it is easily overcome by braking and does not become obvious. I can see how you may conclude that it is not in fact the case, but you are in error on that point.

_Quote, originally posted by *MisterJJ* »_I'm 1000% sure that it is not intended to be shifted into N at every stoplight.

Please carefully re-read both the article and my wording on the subject. -It is NOT necessary to shift at EVERY stoplight, but for extended stationary periods, it is suggested or perhaps 'recommended'.
Keith


_Modified by VWAddict at 12:48 PM 5/15/2009_


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## UnsavedOne (Jan 17, 2006)

*Re: (fs454)*


_Quote, originally posted by *fs454* »_
unpossible?

Sorry? Was that UNpossible?


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## MisterJJ (Jul 28, 2005)

*Re: DSG - Shifting into neutral whenever stopped? (VWAddict)*


_Quote, originally posted by *VWAddict* »_
Please carefully re-read both the article and my wording on the subject. -It is NOT necessary to shift at EVERY stoplight, but for extended stationary periods, it is suggested or perhaps 'recommended'.


Okay, I re-read it. In reference to the "N" position, the article states; "This position should be used when the motor vehicle is stationary for ANY period of time, such as red TRAFFIC LIGHTS, or waiting in a queue of stationary traffic." (Emphasis added)
IMHO, this is totally false. Therefore I would be inclined to believe that whoever wrote it is not stating facts, but they are simply writing what they THINK is correct. I.E. Talking out of their lower orifice.


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## VWAddict (Jun 12, 1999)

*Re: DSG - Shifting into neutral whenever stopped? (MisterJJ)*

It does say that, doesn't it. -Then I agree with you that it's probably misleadingly written in that respect. I have no idea who wrote it... but if it were my choice, I would have included the word 'significant' to read: <_This position should be used when the motor vehicle is stationary for ANY *significant* period of time..._
...however...

_Quote »_IMHO...

While I respect both, I'll always take a 'fact' over an 'opinion'; -even an 'honest opinion'. Everyone is of course entitled to their opinion, but it's risky presenting it on a forum where another reader -with no actual knowledge of what's actually happening inside the box- may take it as informed fact... 
Here are some other easy-to-perform tests which together demonstrate that there is NO further disengagement with increasing brake pressure:
With the engine fully warmed up and idling, and the A/C switched OFF (to reduce another potentially self-varying engine load) apply sufficient brake pressure to hold the car stationary in drive -but no more pressure-
1) slip the car between drive and neutral a few times, and watch the rev counter kick ever-so-slightly as the engine self-adjusts to compensate for the slight load differences between the complete disengagement of 'N' and the partial engagement of 'D'.
2) Once you're familiar with what the slight 'kick looks like, put the car in Neutral, and apply the brake pedal slightly, then watch the rev counter as you go from light brake pedal pressure to full 'lift-your-butt-off-the-seat' pedal pressure, and back to light pressure again. (this is to confirm that the slight alteration in manifold pressure as the brake vacuum servo assist draws a small amount of vacuum from the inlet manifold. (Note: be sure that the edge of your shoe-sole DOESN'T contact the accelerator pedal!) -You should see NO significant tachometer needle movement throughout the range of pedal pressure. -Do the same test 'stamping' the pressure up, if you wish, and again observe the tachometer needle behaviour.
3) Now repeat the same test in 'D'. Going into 'D' you should see the needle 'kick' very slightly as the clutch pack engages slightly, and the engine management adjusts to maintain the overall idle speed at the prescribed RPM against the resulting slight increase in engine load. Now, repeat the brake pedal pressure test, and watch the tachometer again. -Now, *IF* the controller governing the DSG really DID "let go compeltely" when the brake pedal is mashed down, you'd expect to see the SAME slight 'needle-kick' as it did so, and another as you eased the pedal pressure again.
...But it DOESN'T happen.
It behaves precisely as if the clutch remains partially engaged throughout the pedal pressure range... and with good reason. -the '1st-gear' clutch remains partially engaged at ALL times in D while the car is fully stationary- Even when you're trying to push the pedal through the floorpan.
Keith


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## yam (Jul 18, 2005)

*Re: DSG - Shifting into neutral whenever stopped? (VWAddict)*


_Quote, originally posted by *VWAddict* »_
It behaves precisely as if the clutch remains partially engaged throughout the pedal pressure range... and with good reason. 


x2. I experience the same phenomena and have always believed the clutch pack to be slightly engaged when in D but at a stop. One other reason is when I'm on a slight incline, the car will still pull forward with the brakes partially released. And its definitely not the hill hold assist. I've always put the car in N at extended stoplights. Car just idles smoother, and if you log engine load with vag-com at idle, you'll see it is lower in N than D.
Is it possible the slight engine load (and pull) is due to the fluid friction, but the clutchpacks aren't physically touching yet?


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## tekieru (Oct 3, 2008)

*Re: DSG - Shifting into neutral whenever stopped? (yam)*

it seems like this debate is quite long and there really isn't a right or wrong way. my question is: if you do put the car into neutral and then back into drive, is there a hesitation or bump sound like in other automatics? Is there a weird noise or movement?


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## LWNY (Jul 30, 2008)

*Re: DSG - Shifting into neutral whenever stopped? (tekieru)*


_Quote, originally posted by *tekieru* »_it seems like this debate is quite long and there really isn't a right or wrong way. my question is: if you do put the car into neutral and then back into drive, is there a hesitation or bump sound like in other automatics? Is there a weird noise or movement? 
There is a sound due to the gears being slipped into place, but there won't be a movement since unlike a slushbox which torques the whole engine with its un-disengageable slush-clutch, this trannie doesn't engage until your foot is mostly off the brake.


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## H-ManZX (Oct 17, 2005)

*Re: DSG - Shifting into neutral whenever stopped? (LWNY)*

In an German forum someone who seemed to be working in the VW transmission development explained that the clutch is slightly engaged in "D" even when you are in a full stop. But he claimed the clutches were literally wear-free because they are in an oil bath (that's why there is more than one disc for each set of gears, I suppose) and were tested to last longer than about every other part of the car, even with heavy trailer pulling in the mountains. 
Also there is no mention of this in the manual (for the general, technically not interested customer) and the cars are massively sold to older people as "automatics". I personally would also find it inacceptable to be shifting my car every time I stop.
If the oil in the DSG gets to hot to provide proper lubrication/cooling it will automatically fully disengange and the gears will start flashing in the computer. This is supposed to be happening after about 30 minutes of holding the car in "D". (Which is an almost impossible due-to-traffic scenario).


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## VWAddict (Jun 12, 1999)

*FV-QR*


_Quote, originally posted by *LWNY* »_There is a sound due to the gears being slipped into place, but there won't be a movement since unlike a slushbox which torques the whole engine with its un-disengageable slush-clutch, this trannie doesn't engage until your foot is mostly off the brake.



This is -in a strict sense- inaccurate.
The clutch never fully engages until your foot is COMPLETELY off the brake. -ANY level of brake engagement at near-stop speeds causes a partial disconnect/slippage of the clutch.
In addition, there IS an increased load in 'Drive' with the brake FULLY depressed (you can get an elephant to put his full weight in the pedal if you wish!) -You can see it by the movement of the tachometer needle, you can see it in the vacuum-shift on a boost/vacuum gauge, and you can see it in the VAG-COM measuring blocks, under 'engine load', where you can read an actual value on the load.
There's three indications which suggest that the clutch does NOT fully-disengage when in 'D'. -If you don't have a vacuum/boost gauge or a VAG-COM, I can probably video them both... or even ALL THREE indications if you count the tachometer indications...
All of this being easily, repeatably demonstrable; I'm baffled that you're still posting the inaccurate assertion that there is no clutch engagment when stationary in 'D' with the brakes on. -There IS.
Now, as repeatedly observed and mentioned above, there isn't sufficient clutch drag for there to be a need for sticking it in 'N' every single time the vehicle comes to a halt, but if you really were going to be stuck in a traffic, going nowhere for an hour while the police try deal with a blocked road, but you need the engine running so you can use the A/C... that's a different story. -Yes, you need to be in 'N' or 'P'.
I'm not trying to persecute you or anything... I'm just rather uncomfortable with incorrect information being presented as cold fact.
Keith


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## LWNY (Jul 30, 2008)

*Re: FV-QR (VWAddict)*


_Quote, originally posted by *VWAddict* »_

This is -in a strict sense- inaccurate.
The clutch never fully engages until your foot is COMPLETELY off the brake. -ANY level of brake engagement at near-stop speeds causes a partial disconnect/slippage of the clutch.[/qupte]
It is accurate. You have to release the brake to the point where you hear the click. You foot is still applying some pressure on the brake pedal.


VWAddict said:


> In addition, there IS an increased load in 'Drive' with the brake FULLY depressed (you can get an elephant to put his full weight in the pedal if you wish!) -You can see it by the movement of the tachometer needle, you can see it in the vacuum-shift on a boost/vacuum gauge, and you can see it in the VAG-COM measuring blocks, under 'engine load', where you can read an actual value on the load.
> Keith






VWAddict said:


> Your car might be different from mine since I was never able to reproduce your above steps, either moving the shifter between N and D while applying pressure to the brakes or seeing any movement of the tach.
> If while in D, the clutch plates pressure are light enough that it is in effect slipping on a film of oil, then there is effectively no kinetic energy transferred. The oil at that point is not cooling the plates down, but just acting as a lubrication barrier


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## Audi'sRevenge (Mar 24, 2008)

*Re: FV-QR (VWAddict)*


_Quote, originally posted by *VWAddict* »_
There's three indications which suggest that the clutch does NOT fully-disengage when in 'D'. -If you don't have a vacuum/boost gauge or a VAG-COM, I can probably video them both... or even ALL THREE indications if you count the tachometer indications...

I tend to agree with the assessment/conclusion that the clutch is not fully disengaged when in D, stopped; _but_ I can't say that is always the case. To me, sometimes it is, sometimes it isn't. 
There's times you can come off the brake and not go anywhere for a moment until either creep mode engages or you use the throttle. Sometimes, particularly if HHA doesn't engage, you can even roll backwards a bit before it engages. Other times, however, you can indeed feel the things you say, somewhat like an automatic where you can feel the torque converter doing what it does. Why sometimes it seems to disengage completely and then other times not, I have no idea. I don't get what conditions have to be met for one or the other. It never seems consistent to me...
The other thing is if you hold the brake and open the throttle the car _will_ try to move forward as you rev the engine, slipping the #1 clutch despite the fact that the car knows you're on the brakes. That is actually strange behaviour to me, and the only way it doesn't do this is apparently if you have/use launch control (or use the "ghetto launch control" method).
The clutch _is_ slipping to some degree (perhaps on and off) when stopped in D, I agree; and, as mentioned you can often put the car from D into N while stopped and get a similar feeling to what you get when you remove a torque-converter car from D to N while stopped. 
Along the same line of what H-ManZX said, the other thing to remember is that our cars (well all NA A3s anyway) have _wet_ clutches, so the slipping probably doesn't present that much of a wear issue at all. Afterall VAG does claim they will last the life of the car. If anything there should be no way for the #2 clutch to need replacing as it doesn't even slip at all (I don't think it's capable of doing so by design). As for being stopped for very long periods I would imagine that after a _long_ time, stopped in D, the car will be smart enough to disengage the clutch completely to prevent any greater-than-normal wear.
I wonder though, how the dry-clutch DSG differs in operation?


_Modified by Audi'sRevenge at 8:26 AM 6/5/2009_


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## dreaminga3 (Jan 20, 2009)

+1. I've observed exactly the same behavior Audi'sRevenge.


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## VWAddict (Jun 12, 1999)

*FV-QR*


_Quote, originally posted by *LWNY* »_If while in D, the clutch plates pressure are light enough that it is in effect slipping on a film of oil, then there is effectively no kinetic energy transferred. The oil at that point is not cooling the plates down, but just acting as a lubrication barrier


I think you're a little vague on physical principles here...
Kinetic energy is MOTION. if the car is not moving, then you-re exactly right- no kinetic energy is transferred, but (and this is crucial) we don't CARE about kinetic energy... we care about FORCE. If there is a decellerative FORCE (in this case caused by friction) acting upon the engine output, then it will 'transfer' ANOTHER kind of energy... in this case most likely THERMAL.
If a manual transmission car is stationary, and I let the clutch drag to the point that it's tugging at the brakes, but the brakes are JUST holding... then there's no KINETIC energy being developed... but there sure as hell will be some heat.
Keith


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## yam (Jul 18, 2005)

*FV-QR*

Logged the engine load.
Idle in D - 22%
Idle Neutral - 19%


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## LWNY (Jul 30, 2008)

*Re: FV-QR (VWAddict)*


_Quote, originally posted by *VWAddict* »_
I think you're a little vague on physical principles here...
Kinetic energy is MOTION. if the car is not moving, then you-re exactly right- no kinetic energy is transferred, but (and this is crucial) we don't CARE about kinetic energy... we care about FORCE. If there is a decellerative FORCE (in this case caused by friction) acting upon the engine output, then it will 'transfer' ANOTHER kind of energy... in this case most likely THERMAL.

I was talking about the kinetic energy at the crankshaft being transferred to the transmission gears via the clutch. If at a pressure point where the oil act as a lubricant, then there is very minimal heat generated given that the coefficient of friction is very low.

_Quote, originally posted by *VWAddict* »_If a manual transmission car is stationary, and I let the clutch drag to the point that it's tugging at the brakes, but the brakes are JUST holding... then there's no KINETIC energy being developed... but there sure as hell will be some heat.
Keith
If you got clutch plates made out of teflon or ice, there would be much much less heat developed.


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## VWAddict (Jun 12, 1999)

*Re: FV-QR (yam)*

Yam: -A/C off for that log?
Cheers,

_Quote »_If you got clutch plates made out of teflon or ice...

...then you would have the worst clutch in the world. -One which wouldn't work. -Why not consider making a chocolate teapot? -It would be about as much use.
Keith


_Modified by VWAddict at 4:04 PM 6/5/2009_


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## yam (Jul 18, 2005)

*FV-QR*

A/C was off. Just happened to check since I got a CEL.


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## Tcardio (Mar 19, 2009)

wow, I just wasted 5 min of my life reading this thread


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