Audi A3 - VAG DSG gearbox question.

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Sun 9 Aug 2015 19:38
Audi A3 - VAG DSG gearbox question. - bernie123

This question would apply to any car from the VAG group with the DSG gearbox.

In operation when one gear is selected and engaged ie clutch closed, a second gear is also engaged in readiness but with its corresponding clutch disengaged ie held open.

If that open clutch were to suddenly engage because of a hydraulic failure or whatever operates it, the two gear shafts would be engaged together and therefore would lock up the gearbox.

Is this possible because the thought of it happening at speed on a busy road could have devastating consequences.

I don't have one of these and probably wouldn't because of what I have read regarding slow speed lurching and possible mechanical problems out of warranty but was just wondering idly about this.

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Sun 9 Aug 2015 19:52
Audi A3 - VAG DSG gearbox question. - Oli rag

I've no idea in reality, but I'd have hoped there was some kind of mechanical fail safe to stop this kind of fault occuring.

Mind you there might well not be, and when you take it to the dealer with an exploded gearbox they then say " we've never seen that happen before, it's an isolated incident" while passing you the £3000 bill!

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Sun 9 Aug 2015 20:03
Audi A3 - VAG DSG gearbox question. - bernie123

"Is this possible because the thought of it happening at speed on a busy road could have devastating consequences"

This doesn't read right but you know what I mean.

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Sun 9 Aug 2015 21:46
Audi A3 - VAG DSG gearbox question. - elekie&a/c doctor

Can't help with an answer,but a lot of info on how it works here;www.volkspage.net/technik/ssp/ssp/SSP_308.pdf

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Sun 9 Aug 2015 21:51
Audi A3 - VAG DSG gearbox question. - medview

Hi Gents

As a DSG owner I have read up on the transmission. The default state is both clutches open so this state can be initiated by the ECU in a fault condition and the car just rolls to a halt. Neutral can also be selected at any time using the gear selector and then the car just coasts like a manual. I do use this sometimes to avoid downshifts when I know I'm stopping.

I've never head of a lockup occurring as you describe.

The DSG is mostly a great transmission but I'd rather have a torque converter auto, it's just a pity that VAG have given up on such transmissions in Europe.

I too have fears as my extended warrantee end point nears (4years old).

I'm on my second clutch pack at 38000 miles; 61 1.4TSI 7sp.

Joe

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Mon 10 Aug 2015 08:29
Audi A3 - VAG DSG gearbox question. - bernie123

Having a quick shufty at that PDF (thanks) I gather that the two clutches are actually open in their resting state ( opposite to a conventional clutch) and that they are held closed with oil pressure, so if a failure occurs then they would both open.

Much more complex than I imagined and would be a big worry out of warranty. If I buy one then it will be a manual for sure as I tend to keep my cars for many years.

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Mon 10 Aug 2015 18:09
Audi A3 - VAG DSG gearbox question. - ggh1

Years ago when VW first announced the 6 speed wet clutch DSG gearbox I saw a photo (I think on the net) of said gearbox that had selected two gears at the same time, the box had split into two parts!

I hope VW have fixed that problem by now as I am awaiting delivery of a new Golf R DSG.

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Tue 11 Aug 2015 10:48
Audi A3 - VAG DSG gearbox question. - slkfanboy

As above looking at the PDF it looks like that neither clutch would engage. Amazing complex far more so I imaged and an old style auto.

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