Auto DSG box

[Jimbo1959]

I recently read an article, can't remember where though, (God, advancing senility's a pita), I can't remember if it was a Porsche or VW Group article, anyway, to the point.

The DSG gearbox's reliability was being discussed and consequently being ripped apart.

The gist of the story was that this was due to the 'box being used in full auto mode rather than semi auto, flappy paddle mode' and how the box was designed mainly for flappy paddle use.


This made me begin to worry about the flappy paddle arrangement in my Coupe which has the 7G box I'm told.

When I bought it, the vendor said " Just stick it in Auto mode and let the box do the work".

So, query?

Is the 7G box of the same type or similar in operation to the DSG box?
And, do I need to use the paddles from time to time, on the use it or, lose it principle?
Or, was I indeed, given good advice at purchase?

Any info greatly received.

 

[grahamcol]

Dunno but my mate has an Audi TT and his DSG box has become problematic at around 60 k odd miles. Hopefully Mercs will fare rather better and certainly my W202 C200 (written off e or 4 years ago due to an accident) with the 722.6 autobox was fine at over 150k miles. No flappy paddles mind you.

 

[LostKiwi]

The 7G box is a proper automatic transmission with (excepting a few special versions for AMGs) a normal torque converter. DSGs don't have a torque converter.
The dry clutch DSG gearbox is particularly unreliable.

 

[Xtractorfan]

DSG is basically 2 manual boxes combined in one housing ... it is actually two gearboxes synchronised to work in conjunction with each other, DSG changes much quicker and in full flight mode changes should be only noticeable by keeping a sharp eye on the rev counter. Basically, the DSG will already have selected the next gear before it is needed and the change becomes smooth and un-noticeable... If you can imagine 2,4,6, (gears) in one box and 1,3,5,7 in the other. This means that the next gear is preselected by the electronics before the gear is actually needed, and takes over instantaneously as soon as it is needed.
The biggest problem is maintaining the two boxes in synch, as the least variable can cause problems.
And each box having it's own clutch doubles the possibility of trouble in that department.

 

[JBell]

The main problem with the DSG boxes is the Mechatronic unit that controls it, VAG had massive problems with them and initially refused to replace them even though it was a well known problem, class action in the US soon sorted that out!!!

They are apparently now lunching themselves through being always used in auto.

The Porsche PDK 'box is basically the same

 

[Jimbo1959]

The 7G box is a proper automatic transmission with (excepting a few special versions for AMGs) a normal torque converter. DSGs don't have a torque converter.
The dry clutch DSG gearbox is particularly unreliable.

Phew! Thanks Alistair, that's a relief.

So, the info I was given at purchase was bona fide and I can use (or not) the flappy paddles without worrying about it then.

That's a weight off my mind.

 

[Botus]

its not rocket science, on DSG gearboxes the clutch unit is more complex, more delicate and there's more electronics,

both ford and VAG had issues with oil leaks / spec of the oil used, that didn't do anything any favours and the electronic control modules just like any fitted to any make of car is now a designed to fail unit

they do exactly as designed on the electronics front, mechanically the clutch materials and the design needed a few years of development to get them to work well in the real traffic conditions out there.

the modules are easily fixed by the big players designing out the intended time related breakdowns. However one of the biggest issues is retard owners who don't care the change is odd and keep driving till things break. A big win would have been with wear rates being a little higher than envisaged, carrying out the reset / initialisation procedure (so it has a chance at working right) more often than "never".

Ford have now extended the warranty on its DSG gearboxes to 5 years in UK, you may get a new box (oil seal issues on early ones), new clutch plates to the current material spec on most and definitely a software update. ….but most owners just sell the car and the next mug will do exactly nothing to help themselves. From Aug 2016 fords are now robust

On Merc 7G I wouldn't describe them as conventional autos. Yes the principles are exactly that, but they are not made by a competent manufacturer like ZF nor by the way is the 9G box. I was just saying at the weekend as mine made its usual hash of changing gear terribly, why do Merc persist in trying to do gearboxes when there are manufacturers out there who know how to do it properly?

http://www.ecutesting.com/catalogue/ford_eculist.html?category=4061&model=492

http://www.ecutesting.com/catalogue/mercedes_eculist.html?category=4061&model=498

http://www.ecutesting.com/catalogue/volkswagen_eculist.html?category=4078&model=448

 

[Mr Filipov]

its not rocket science, on DSG gearboxes the clutch unit is more complex, more delicate and there's more electronics,

both ford and VAG had issues with oil leaks / spec of the oil used, that didn't do anything any favours and the electronic control modules just like any fitted to any make of car is now a designed to fail unit

they do exactly as designed on the electronics front, mechanically the clutch materials and the design needed a few years of development to get them to work well in the real traffic conditions out there.

the modules are easily fixed by the big players designing out the intended time related breakdowns. However one of the biggest issues is retard owners who don't care the change is odd and keep driving till things break. A big win would have been with wear rates being a little higher than envisaged, carrying out the reset / initialisation procedure (so it has a chance at working right) more often than "never".

Ford have now extended the warranty on its DSG gearboxes to 5 years in UK, you may get a new box (oil seal issues on early ones), new clutch plates to the current material spec on most and definitely a software update. ….but most owners just sell the car and the next mug will do exactly nothing to help themselves. From Aug 2016 fords are now robust

On Merc 7G I wouldn't describe them as conventional autos. Yes the principles are exactly that, but they are not made by a competent manufacturer like ZF nor by the way is the 9G box. I was just saying at the weekend as mine made its usual hash of changing gear terribly, why do Merc persist in trying to do gearboxes when there are manufacturers out there who know how to do it properly?

http://www.ecutesting.com/catalogue/ford_eculist.html?category=4061&model=492

http://www.ecutesting.com/catalogue/mercedes_eculist.html?category=4061&model=498

http://www.ecutesting.com/catalogue/volkswagen_eculist.html?category=4078&model=448

All I can say about the ZF box after living with the BMW for 4 months now is that box is phenomenal. Going from a 7G and even tested a 9G, they have not got a patch on that 8 speed.

 

[alexanderfoti]

its not rocket science, on DSG gearboxes the clutch unit is more complex, more delicate and there's more electronics,

both ford and VAG had issues with oil leaks / spec of the oil used, that didn't do anything any favours and the electronic control modules just like any fitted to any make of car is now a designed to fail unit

they do exactly as designed on the electronics front, mechanically the clutch materials and the design needed a few years of development to get them to work well in the real traffic conditions out there.

the modules are easily fixed by the big players designing out the intended time related breakdowns. However one of the biggest issues is retard owners who don't care the change is odd and keep driving till things break. A big win would have been with wear rates being a little higher than envisaged, carrying out the reset / initialisation procedure (so it has a chance at working right) more often than "never".

Ford have now extended the warranty on its DSG gearboxes to 5 years in UK, you may get a new box (oil seal issues on early ones), new clutch plates to the current material spec on most and definitely a software update. ….but most owners just sell the car and the next mug will do exactly nothing to help themselves. From Aug 2016 fords are now robust

On Merc 7G I wouldn't describe them as conventional autos. Yes the principles are exactly that, but they are not made by a competent manufacturer like ZF nor by the way is the 9G box. I was just saying at the weekend as mine made its usual hash of changing gear terribly, why do Merc persist in trying to do gearboxes when there are manufacturers out there who know how to do it properly?

http://www.ecutesting.com/catalogue/ford_eculist.html?category=4061&model=492

http://www.ecutesting.com/catalogue/mercedes_eculist.html?category=4061&model=498

http://www.ecutesting.com/catalogue/volkswagen_eculist.html?category=4078&model=448

I find all my MB boxes really smooth, apart from the 2-1 change in the MCT 7g on the C63, other than that is very smooth, and fast, for what it is.
The S class box is now perfect after its overhaul, but, it was introduced in 1996 so has had a long time to be perfected!

 

[John Laidlaw]

Must say no complaints on the 7g MCT which is noticeably quicker than the 7g I previously had in the SL
Ok it is a more brutal change in S or S+ when pushed but there’s a whole load of torque in there

 

[B king]

never had any real problem with my box but, when I accelerate hard, it changes v smoothly but when I take my foot off the loud pedal, after a second theres a big thud from the back ..? I assume this is as the g box puts it into the highest gear,,..and ive no revs on ..?

 

[Botus]

I was telling my passenger about what's wrong with Merc 7G boxes, as we pulled away from some lights one change was nasty and the next poor. After it had warmed up a lot I pulled away mildly briskly and got a rare surprise as the box did a great job and managed 4 in a row that were good.

Next weekend same sort of 20 mile run under its belt, I thought I'd try and replicate the same conditions where I had 4 good changes, only for them all to be a disaster

the solution that seems to solve the issue is turn up the radio and try to ignore it,

when I was working on RR (36 years back) I never came across one like these thing are, if we had a RR that performed like a 7G one does on its best day we'd take the box out pull it to bits and usually throw it in a skip

 

[Capra]

I was telling my passenger about what's wrong with Merc 7G boxes, as we pulled away from some lights one change was nasty and the next poor. After it had warmed up a lot I pulled away mildly briskly and got a rare surprise as the box did a great job and managed 4 in a row that were good.

Next weekend same sort of 20 mile run under its belt, I thought I'd try and replicate the same conditions where I had 4 good changes, only for them all to be a disaster

the solution that seems to solve the issue is turn up the radio and try to ignore it,

when I was working on RR (36 years back) I never came across one like these thing are, if we had a RR that performed like a 7G one does on its best day we'd take the box out pull it to bits and usually throw it in a skip

Sounds a bit dramatic, but if that's your experience then fair enough. Mines been faultless so far, just hope I dont experience your findings

 

[BillyBoy]

If it helps, my GL had a 7G auto box and 255,000 miles on the clock when I sold it and the gearbox was still faultless...

 

[Capra]

If it helps, my GL had a 7G auto box and 255,000 miles on the clock when I sold it and the gearbox was still faultless...

Wow thanks. I know they were not the best, but not terrible by any means. From what I've read they just require correct servicing.

 

[grayb]

When pulling away from a junction, our 7G equipped W212 sometimes takes an alarmingly long time to make up its mind what to do - enough to scare both us and the on-coming traffic sometimes.

 

[JBell]

When pulling away from a junction, our 7G equipped W212 sometimes takes an alarmingly long time to make up its mind what to do - enough to scare both us and the on-coming traffic sometimes.

Use it in S or M and it will respond much faster

 

[EmilysDad]

When pulling away from a junction, our 7G equipped W212 sometimes takes an alarmingly long time to make up its mind what to do - enough to scare both us and the on-coming traffic sometimes.

Don't they set off in 2nd unless in sport?

 

[Naraic]

My 7g never seems to be in the right gear on a light throttle. If travelling at, say, 40 and I push gently on the throttle to gain more speed it seems to remain in the higher gear but without the torque allowing speed to to increase...I have to dab the throttle to make it change down then it pulls better.
So, turning off on to a side road the gearbox needs quite a big prod to allow me to maintain and then gain speed in a reasonably spirited manner...and even then, it's a bit slow at deciding. Not the greatest box...the old 5 speed was better IMO.

 

[Naraic]

Don't they set off in 2nd unless in sport?

I believe so.