DSG Transmission – Explained

DSG Transmission – Explained


[Music] give it a little cool all right Charles time to be serious I’m Jason with engineering explained and hey I’m Charles from humble mechanic comm and in this video we’re gonna be explaining how direct-shift gearbox is work and we’re gonna be starting with the clutch two clutches in fact oh and we’re wearing gloves because Charles is gonna get his hands dirty and I wanted to feel included yeah we got to make sure Jason fits in so it’s a little dangerous usually I just deal with white boards and they’re very safe do my gloves for white boards you get like a little edge yeah I get a little a little fade on my hand and I have a take a shower afterwards to clean up everything too much I don’t know that everybody all right anyway it’s back to the clutch all right so this is actually the dual clutch pack out of a Volkswagen transmission this particular one came out of a I want to say a 2013 Passat normally this isn’t something that I’m able to keep it has a core charge on it but but you stole it but I did not steal anything nothing was stolen in the making of this video okay this actually the customer hid something and I was able to the customer hit something yeah I was able to keep this this is really cool we’re excited to kind of explain how this works and show you guys all about the dual clutch so this is the clutch housing and this is gonna be rotating with the flywheel in this case it’s a dual mass flywheel that this bolts up to and both clutch packs are inside of this so and these are multi-plate clutches so I’ll let Charles explain what’s going on in the inside here so basically what happens is there’s two like jason said there’s two clutches there’s an inner in an outer clutch volkswagen cause these k1 and k2 k1 controls the odd gears and k2 controls the even gears now there’s an electronic unit that controls the fluid flow to this and what it’ll do even though this entire mass is rotating with the flywheel it can lock one or either the inner clutch or the outer clutch and rotate one of two input shafts to the transmission so we’re looking at the overall gear set of this transmission you can see it’s basically a manual transmission this is our two input shafts you can see that I’m rotating this one independent from this one and that’s where the that’s where the dual clutch comes in one clutch controls one the other clutch control this is two separate shafts right here though they’re concentric they’re one on top of the other if this were a traditional manual transmission this would all be one for one-piece okay so this is the input shaft for the transmission and it’s actually two shafts as we mentioned earlier so one is around the other and basically what happens is you’ve gotten these two clutches here now this right here which splines to one of the shafts this one rotates the inner clutch as you can see there and then this outer piece of housing here rotates the outer clutch so what happens is when you stick this on here you can see that it only rotates with the upper shaft and then as I take this and put that on top that rotates with the other shaft so that’s how you’re controlling the odd years and even gears with these two shafts so here’s a more detailed look at these multi-plate clutches now these are wet clutches which means they are housed in oil and as you can see here you’ve got the alternating friction discs and plates this is the inner clutch and then you’ve got the same thing for the outer clutch so here you can see the outer shaft which rotates with the inner clutch and then the inner shaft which rotates with the outer clutch as we rotate it around we have the output shaft number one and this has gears one two three and four these are the selectors that control the collars they sit in the tubes right over here and for example that would be first gear we’re already engaged in the second gear so how do you know which gear you’re looking at here so when it comes to a manual transmission the bigger and size the gear the lower the gear number so this is going to be first gear second gears down at the bottom then we go third four and five and six are actually on output shaft number two okay as we rotate this around we come around to the differential and I set the axial cup in here just to kind of give an example of where the axial would be in relation to this entire transmission now we actually have the second half of the case completely removed just so you guys can see this obviously it’s all in case you wouldn’t be able to see anything if we had both cases installed as we come around here’s output shaft number two and this has reverse five and six and they’re actually different size collars so we engage this is actually a broken transmission but we engage gears this way here’s reverse engaged down there this is your reversed shaft remember we have to rotate the gears the opposite way when direct going backwards as we come back around one really cool thing is there’s these wheels all throughout these gear sets and this actually lets the the mechatronic unit know exactly where each position is and what’s rotating and at what speed and it’s really fun to plan it this is the selector that’s used to select each gear there’s little Pistons inside the case one will move it up and then on the corresponding side on the top will move it down and this piece right here is actually a magnetic position sensor so the mechatronic unit knows exactly where each selector is throughout the process so you can see here we have first gear engaged I’m actually turning the input shaft of the transmission this is actually input shaft one and so here’s the output going to the differential which will then send power to the driven wheels right so power flow is coming actually from the back here up to this gear you can see at the very top of your screen that I’m turning to gear was down to the differential and then out to the wheels your wheels would actually be here and then the opposite spot on the bottom of the screen so if we’re to run through if we’re to engage first gear so everything’s gonna be nothing’s gonna be selected when we’re selecting first gear this color here will engage first gear and then you’re sending power to the wheels with first gear engage now while you’re doing this as you’re starting it to the higher rpms and the clutch is anticipating you shifting the second the second gear collar will engage while the first gear is still engaged but remember the clutch that this second gear is engaged to is disengaged from the engine whereas this one is engaged so once you actually do shift gears you tell the computer hey switch gears you press on a paddle shifter or whatever it may be then this will disconnect and all the while your clutches are switching which ones sending power to this differential here so this one will start receiving power while this one is still receiving power and you’ll kind of have this overlap of where you’re always going to be getting torque but that torque is going to decrease from this one and increase this one and then send power to the driven wheels through this differential and that is why a DSG will always shift faster definitely better than a manual car or a automatic gearbox with traditional planetary gears because you’re always going to have some torque being delivered and you can pre-select the next gear up or the next gear down depending on what the computer thinks you’re going to be doing next and that allows you to have a much quicker shift so what I have in front of me here is the mechatronics unit and basically what this is responsible for is the logic for the transmission so you may be wondering how does it know which gear to pre-select and there’s some logic that goes into that and basically some simple examples are let’s say you’re in second gear and you’re flooring it the RPMs are increasing it’s gonna go ahead and press select the higher gear third gear so you can get into that one very quickly let’s say you’re in fifth gear and you’re hard on the brakes well then it knows to downshift for the next one so it will go ahead and pre-select fourth gear and I think that really explains why there’s some sort of misconceptions about you know this transmission itself because this is a manual transmission that just happens to be automatically controlled so that may explain why you know certain criteria of driving may a driver may experience you know a delay or a weird shift because the computer brain right here can really only predict a driver’s input to a certain right so if it pre selects the wrong here and you chose to go the other direction with the gear shift then you may feel you know a slight delay because it has to compensate for that change my experience that really shows itself when you’re accelerating and let’s say the light turns red and you let off the gas and you know magically the light turns green really fast you hit the gas again that’s when you really experience that delay because the transmission computer thinks you’re gonna do one thing because it’s seen you know a series of seconds go by with this input from the driver and now the driver flips that on its head and matches the throttle now the transmission has that split-second of I don’t know what to do oh okay now I’m good let’s go and that’s I think where a lot of people sort of have this conception of a DSG being you know jerky or finicky or whatnot so thank you guys for watching if you have any questions or comments you know what to do and thank you Charles for having me here I flew all the way from Oregon to North Carolina just to check this guy out yeah let’s get watched our video on the vr6 you should check that out that’s a great video I think it broke the internet broke the internet but in that / – yeah way better than that other yeah anyway guys thanks for watching and we will see you next time

Danny Hutson

100 thoughts on “DSG Transmission – Explained

  1. My question is : does a DCT needs a torque converter or it is engaged directly to the engine through multi plate wet type clutch?

  2. 2019 and we're still using metal on metal gear driven mechanisms. Should be using tube technology! Most engines are still held together by a big rubber band.

  3. In 10 minutes I learned how car companies fixed something that was not broken. My Honda conventional automatic has 255K miles and still has no problems… another stick I had had 380K miles and needed one clutch. Cost to replace: $198 dollars. You can keep this junk… nothing personal.

  4. I have a VW Up! (Not sure if sold in the USA) which has a ASG gearbox, it’s been described to me as a automated manual gearbox…is it similar to the DSG?

  5. Damn, when you see the parts and complexity, it gives me an appreciation of the cost to work on these. I wont feel so bad when my wifes clutch blows out!!!

  6. The mechatronic of my DSG gearbox actually broke down.. i got it fixed by the dealership. But how is it possible that this specific unit can become broken? What could be the cause?

  7. If they want to make a transmission that behaves like a manual transmission, why not just put a manual transmission in the thing?

  8. This was very interesting. But how does it shift so smoothly? In a manual, if you drop the clutch, you get jolted back, but here it doesn't happen. Does it double clutch automatically or simply, since the gear change happen so quickly, the RPMs don't drop?

  9. New 2011 1.6 Tdi Skoda Octavia with DSG 1) Clutch breaks within the 1st year (replaced the whole clutch) 2) Clutch breaks again on the 4th year (they changed only the even gears) 3) Varta battery blows up, ECU of gearbox burns up they replaced the ECU and changed the oil into a brand new one recommended by the company….6 years on and I have a judder when I move from 3rd gear to 2nd gear but the gearbox holds up for the moment. Compare this gearbox with my 25-year-old supercharged 4 speed auto honda and you can tell this gearbox is s**t.

  10. Sometimes I can feel my car (2012 VW CC) trying to pull forward when I'm stopped, even with my foot on the brake. I assume that means the DSG is riding the clutch slightly, which is something you don't normally want to do. Other times, I can tell that the car has done its best to release the clutch entirely while I'm stopped, and when I take my foot off the brake on those occasions, I can feel a slight delay before the clutch engages.

    For that reason, I like to shift to neutral at stops, since I can't disengage the clutch "manually" any other way. Is that a big no-no? I'm wondering about mechanical issues, not "best practice" driving technique. In fact, my sense is that the car shifts into first and takes off faster when I hit Drive and go. The car sometimes takes much longer to engage if it's in already in Drive but has decided to disengage.

    Probably will keep doing it unless I hear a well-reasoned argument against. I like feeling "in control."

    Has anyone seen a VW white paper on how to drive the DSG to best advantage?

  11. would you say the jerkiness also appears on the DSG if you begin to accelerate and the quickly decide to stop hard?

  12. This is a very good explanation. I just bought a 2014 Jetta TDI with this transmission. It takes a bit of practice to drive it smoothly, but it does work.

  13. I hear you but dont understand….this box is very clever.
    I wonder how long it took the vw engineers to crack their first DSG gearbox…….
    Witchcraft.

  14. Gerçekten çok güzel videolar çekiyorsunuz Hepinize çok teşekkür ederim Türkiye'den selam Oto Servis olarak sizlere takdir ediyorum

  15. Finally, after a couple of years since having seen this video my mechanisms professor has told me to see this video in order to understand dsg's.

  16. Nice job tag-teaming and explaining the DSG. As one with auto and manual trans experience in a previous life, everthing made perfect sense! 😀 I WAS disappointed not to see a duet from you two as an encore! 😉

  17. I love mine. Works like a charm. 45K miles so far. I've heard bad things about the ones from other manufacturers, but VWAG seems to have it right.

    Do NOT skimp on maintenance. Change the fluid at the recommended intervals. And drive it like a stick. Don't just pound the pedal like you have a slushbox.

  18. This did not explain the main weakness of dual clutch gearboxes, stop and go traffic causing overheating and premature failures.

  19. Which automatic gear box used in benz,bmw,jagur,ferrari etc..
    is it planetary type gear box ?
    Now is any planetary gear box used in any vehicle

  20. I have a 2.0tsi scirocco and id like to know if it pre engages gears BELOW the gear your in. For example, I am coming up to a hill and downshift manually from third to second, will second gear already have power applied to it or is the pre engagement only on upshifts?

  21. Can I just say a massive thank you for helping me out with my college transmissions essay. Really couldn't understand it before!

  22. i've seen flywheels of many jetta's and passat's rattling and at 15000 miles an then cost a bomb to replace. any idea why so many premature failures?

  23. DSGを採用する車はこのようにドライブトレインが非常に重くなる。だから高価な馬力(トルク)のある車にしかつかないんですな。
    F1のを見たけどフォークシャフトに工夫がされている。これを一般車に簡易的なものとしてできんものだろうか。Thank you.

  24. VW needs to know we need very very very very reliable cars and not cars that shift faster, car technology has come so far and drivers have no idea about what is underneath the hood, and couldn't care less, we are curious yes, but when it comes to buy a car reliability is very important, what is the point of having a car that shifts faster when you can not even drive that car cause breaks down all the time and plus is very expensive to fix and plus is hard to find mechanics to fix it, why this companies sell this disposable cars to us??? I guess profits… oh well , answer was not that hard

  25. OMG. So complex and efficiency lost because of all the gears friction. Pure electric motors definitely win in this department I’d reckon. Thanks for explaining though

  26. In theory could a DSG be given a fly by wire clutch as it were that could be used to manually operate the clutch if desired? Does the mechatronics unit (as VW call it) have the ability to provide that level of control if it were to be manually operated?

  27. motorcycles and indy cars been using this setup for many years. one example is the VFR uses a similar set up, and its pretty cool.

  28. Can see why you have so maby subs another great video its a little bit like a bike clutch with the basket and the individual steel and friction plates in oil

  29. Hello sir
    I wanna ask , if my clutch pack cover leak
    It can cause my car wont shift up from 1 to 2
    My car 2010 gti mk6
    Please reply thanks

  30. I’ve been trying to wrap my brain around auto transmissions for 25 years. Still doesn’t make sense. But I like shiny!

  31. Hi guys, nice vido. Only one correction: the even gears are on one shaft while the oneven gears are on the other shaft. Otherwise it could never preselect a gear while another gear on the same shaft is selected. What it dus is while disingeging one clutch it ingeges the other. Therefore seamles shifting.

  32. Thanks for the awesome info.
    I am considering buying a wrecked 2011 Volkswagen Jetta TDI and I am trying to learn all I can.
    The car is an easy rebuild, but friends at a foreign auto shop said beware of the DSG Trans.
    I personally think it is a brilliant design, but only if totally durable.

  33. For someone new to the auto world, about 6 months now, I'll have to admit at times I struggle to grasp what's being explained or shown. So whenever that happens I just make sure I return to watch and listen again every few days or so. But with this I'm watched it probably 8-10 times over the last few months and understand most of the lesson but not all. The part I've struggled with the most is correlating the visual workings of the dsg in this video, but as of right now it just freaking clicked. So stoked

  34. I am amazed at how well you explained that! I have always had a vague explanation from others, and as an engineer it always bugged me. Great explanation, and having one to SHOW was amazing.

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