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Hi All:

___Read this one this morning: 2009 Volkswagen Jetta TDI: Smiles, not smells, in this sporty four-door (boston.com/cars/newsandreviews/overdrive/2009/03/review_2009_vw_jetta_tdi_part2.html)
Come to a stop, however, and the Jetta’s smooth demeanor vanishes and the quality controversies reappear. At first you’ll think the only jerk in the car is you – after all, every brake pedal has a different initial bite and feel. But after a few more times, the culprit becomes obvious: it’s the 6-speed Direct Shift Gearbox, Volkswagen’s version of the latest transmission fad, the dual-clutch automatic.

The dual-clutch is a true hybrid transmission. It shifts automatically, but unlike a conventional automatic, there’s no torque converter. Instead, the gearbox is divided in two: one clutch controls the odd gears, while another controls the even gears. During a shift, the inactive clutch pre-engages the next gear while the active clutch disengages the current gear. This results in quicker upshifts without the lag of a typical automatic, or the momentary cutoff in fuel as required by a manual.

On paper, it sounds great to have this advanced gearbox in an average car, the same in principle as the 7-speeds on the latest Porsche 911 and Volkswagen’s 253-mile-per-hour Bugatti Veyron. On the way up, shifts are indeed quick and smooth, delightful even, thanks to the diesel four-cylinder’s generous 236 pound-feet of torque. But like a drug addict, the high literally comes crashing down.

In every transmission mode, the DSG delivers abrupt downshifts from third gear. It's mild for the most part, but the forced engine braking ruins the ability to coast and stop gently, even with the lightest of brake pressure. Stop-and-go traffic makes you realize what it’s like to be a bobble-head doll, and the DSG even has the audacity to shift into first while the car is still moving. There’s no rev-matching feature to abate the feeling, and it never goes away. Granted, it’s helpful for engine braking, but that should be the sole job of the Tiptronic mode. In short, the DSG - at least in the Jetta TDI - feels sloppy and better suited for high-performance cars where a jerky ride is more of an expected shortcoming. Volkswagen has introduced an improved 7-speed DSG for its Passat CC sedan in Europe, but we'll have to wait a while before it arrives here.
After a full week of daily driving in our 2009 Jetta TDI, I began to forgive the DSG transmission for some of its jerky behavior. I learned to anticipate gear changes ahead of time, which made it much more tolerable (but still not acceptable, in my opinion).
___Good Luck

___Wayne

There's a thread in VW Vortex about problems with DSG, generally:

http://forums.vwvortex.com/zerothread?id=3968936

Seem to be a lot of discussion about the "mechatronic" unit needing to be fixed/replaced?

Good lord. If I ever threaten to buy a car that requires a grand-plus worth or "regular maintenance" at 40k intervals, please lock me up until the feeling passes.

Well, at least now we know why VW's free maintenance plan ends at 3 years/36k miles. ;)

On the other hand, the thread does ask for owners to post complaints, and considering it's been open since last year, I'm surprised there aren't more posts.

On the other other hand, this is still the sort of stuff that makes me skittish about buying VW.

There's been a bit of discussion on tdiclub about the 2009 DSG shifting violently and sometimes not engaging properly. Dealers seem to be targeting the mechatronics unit for replacement.

I don't know about the DSG, but the 5 spd manual is sweet.

Hi Jud:

___The older 5-speed and new 6-speed sticks should be. I had never heard or looked into the DSG AT having a problem until this morning however?

___All, is the DSG working smoothly after repairs? This could bode poorly on a number of future vehicles that will be DSG equipped including any number of Ford's currently being fitted with them for 2010 - 2012 releases.

___Good Luck

___Wayne

The previous DSG TDI did not seem to have these issues. I'm seeing a lot more talk on the DSG and rough shifts with the new engine than the old one. I don't know much about the 2.0T, but on the TDI side of things, some have seen improvement from replacing the mechatronics unit or sensors connected to it, but some have not. My understanding of the mechatronics is that it's basically the brains, sensors, and valve bodies that make decisions when to shift and then reroute transmission fluid to make it happen. So replacing the mechatronics unit sounds like just a shot in the dark hoping to hit the target which is causing the problem.

It could well be that the issues are software based instead of the mechatronic. A few members heard there may be a flash update available soon.

Is it possible to coast in neutral with the DSG?? In other words, is N-ICE ON possible with it??

How about FAS: is that possible with it??

How about bump starting??

Less importantly, can you shift it from one gear to any other as you would a manual?? Say fifth to second, or second to fourth?? Is skipping gears possible??

I do these things all the time with normal MT's, so I'm wondering.

Hi John:

___The TDI manual states it can be flat towed IIRC which means both FAS' and of course NICE-On's are fair game. I would still like to run the TDI w/ a DSG through a FAS cycle at various speeds just to see how it feels however given the above.

___Mike thanks for the details. If its SW, that one is an easy fix and I hope Getrag (I think that is who makes the TDI’s DSG?) has it figured out.

___Good Luck

___Wayne

And that's whey we should all learn how to drive manuals in this country (ie USA).

John, imagine the DSG as a more sophisticated sequential manual transmission. Controlling it manually with the paddles or whatever, it's probably not possible to skip gears. The auto mode may allow skipping gears, but then it's the computer deciding that and not you. I don't believe that it can be bump started.

Wayne, it's Borg-Warner who makes the DSG's. I too hope that either BW or VW figure out what the issue is, and quickly.

jhu, I agree with you on learning how to use manuals. The DSG is a great idea for those who need an automatic, but giving up the control of a full manual and the 40k mile service intervals would bother me. I'll stick to manual transmissions if I can.

John, imagine the DSG as a more sophisticated sequential manual transmission. Controlling it manually with the paddles or whatever, it's probably not possible to skip gears. The auto mode may allow skipping gears, but then it's the computer deciding that and not you. I don't believe that it can be bump started.

Wayne, it's Borg-Warner who makes the DSG's. I too hope that either BW or VW figure out what the issue is, and quickly.

jhu, I agree with you on learning how to use manuals. The DSG is a great idea for those who need an automatic, but giving up the control of a full manual and the 40k mile service intervals would bother me. I'll stick to manual transmissions if I can.

Ah yes, the higher maintenance costs of a DSG. I don't think they're really worth it.

Good lord. If I ever threaten to buy a car that requires a grand-plus worth or "regular maintenance" at 40k intervals, please lock me up until the feeling passes.
I'll just put a boot on your Prius and hold that title for you for a fortnight. :)

what pisses me off is that the dsg's are faster 0-60 than the regular 6spd.

If you watch the 09 TDI videos on youtube, the dsg is clocked at 8.5 sec while the regular 6spd is clocked at 10 seconds. Big difference, my theory is the manny trannies are fitted with a heavier flywheel, so when you shift the revs drop really slow compared to the dsg.

Plus two clutches shift faster than one =\, at least that 1 mpg gain goes somewhere I guess.

John, imagine the DSG as a more sophisticated sequential manual transmission. Controlling it manually with the paddles or whatever, it's probably not possible to skip gears. The auto mode may allow skipping gears, but then it's the computer deciding that and not you. I don't believe that it can be bump started.

So suppose we're rolling along at 60mph in 6th with a DSG, come to a nice juicy downgrade, and want to FAS or coast N-ICE ON. How do we get to neutral? I'm guessing it will allow us to slide a lever to N or do something with the paddles but does anybody know for sure? [On a motorcycle's sequential gearbox there are no neutrals between gears except between 1st and 2nd.]

Now that we're coasting along, what happens to the DSG if we key off? Will it tolerate that?? Without wear?? Are the values in its "brain" lost?? Is this hard on its electronics??

OK, we've finished our FAS, are rolling along at 45mph on the highway, and want to initiate a pulse. We can't bump start, so we key start [battery usage!]. And then what?? Can we shift it back into "D" while it is moving?? Without having it hunt for the right gear?? Without wear?? Can we paddle it into the gear we want?? Will trying to rev-match while doing this confuse the DSG into downshifting??

I don't know the answers but they seem important to the functionality of the DSG powertrain for HM purposes?? I've used sequential manual transmissions (motorcycles) for ca 25 years and am very well aware of the shortcomings of sequential transmissions, which is why I'm asking these questions.

Yes the DSG may be a bit better than a manual sequential, but STM it's less sophisticated than a normal MT if we can't bump start it and can't skip gears. Even if it would let us skip gears, using paddles and watching a gear indicator is much more fussy than simply putting the lever into the gear you want and keeping your eyes on the road.

From what has been written, it appears that DSG will deliver significantly better FE than a conventional AT for people who just push on the gas pedal. How that will balance out WRT added cost, weight, and complexity is unclear. And reliability is unclear, may take a while to work the bugs out. From a cynical viewpoint, it's probably a good way for mfr's to improve FE while still collecting the upcharge for "AT".

As for speed of shifting, that seems irrelevant on the road (though very important on the racetrack). Certainly irrelevant for someone trying to maximize mpg.

You could ask Vooch to be sure, but there is an N position on the gear selector so putting it to N should move you to neutral without having to run through the gears. Now that I think of it, I don't even think the DSG can be flat towed. I recall reading that it uses a fluid pump driven by the engine.

Hi Mike:

___In the 09 Jetta TDI manual, I am almost positive it said it could be flat towed below 45 mph. It has been some time since TDIFest however.

___Good Luck

___Wayne

Maybe I'll ask on tdiclub to try to confirm. The post I saw about the fluid pump was not for the 2009.

The response was that the the 2009 DSG should only be towed for distances less than 30 miles or transmission damage could occur. Sounds ambiguous to me, but at least it can be done.

what pisses me off is that the dsg's are faster 0-60 than the regular 6spd.

If you watch the 09 TDI videos on youtube, the dsg is clocked at 8.5 sec while the regular 6spd is clocked at 10 seconds. Big difference, my theory is the manny trannies are fitted with a heavier flywheel, so when you shift the revs drop really slow compared to the dsg.

Plus two clutches shift faster than one =\, at least that 1 mpg gain goes somewhere I guess.

I don't think those figures are correct. The DSG may by slightly quicker, but no way 1.5 sec. unless the manual driver is not launching or shifting correctly. The DSG is somewhat heavier, shifts a bit quicker, but not 0.75 sec per shift quicker. There are only two shifts between 0 and 60 mph, and gearing is similar between the two gearboxes. I find my 6-speed manual can be shifted very quickly.

The official VW UK web site shows equal 0-62 mph (100 km/hr) times for the DSG and manual Golf Estate (=Jetta Sportwagen) 2.0 TDI, 9.7 sec. Probably this is with a non-optimal start.
http://www.volkswagen.co.uk/#/new/golf-estate/which-model/engines/acceleration/
(note that VW US web site is really full of typos and incorrect info in its specifications).

Of course all this is irrelevant to normal driving and fuel efficient driving, where the manual has the advantage. The DSG is more efficient than a normal auto, but it still must maintain hydraulic pressure which takes extra fuel.

I should add an update that msantos and I were able to replicate one of the complaints about rough low speed transitions from the DSG when we had a Jetta for the Canadian Jetta TDI Sedan review (http://www.cleanmpg.com/forums/showthread.php?p=203560). To me, what we experienced felt like rough or sudden re-engagements of the clutch, similar to what a novice manual transmission driver may do at low speeds crawling along. This only occurred in the manual mode, leaving the transmission in drive seemed to eliminate the issue. I think that if I were to leave the transmission in manual mode (possibly not the best choice for fuel economy), I would soon adapt to avoid the circumstances that lead to the roughness. Nevertheless, what we experienced shows that there is some probably fine-tuning that needs to be done in the control software.

I don't understand something. The DSG is supposed to have the mechanical underpinnings of a manual transmission. Why would it then only be flat towable for only a short distance? Does the same hold true for a regular manual transmission car?