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Is a dual-clutch transmission right for you?

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Is a dual-clutch transmission right for you?

 
Old 07-11-2019, 10:39 AM
  #61  
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Originally Posted by RedMercy;[url=tel:1599733293
1599733293[/url]]Didnít you mean you couldnít care less?
Your words not mine. Interpret as you like.
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Old 07-11-2019, 10:46 AM
  #62  
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Originally Posted by 16/C7Z View Post
So many things that will inherently have an issue or 2 (or 10) and this can all go sideways fast.

That's why the safe(r) approach would have been to make the ME with a conventional trans and a manual then offer the DCT and a manual over time. Just my opinion.
I'm really surprised they are betting everything on DCT. With as much change as this car will represent, I'm really surprised they are going this far. It's surprising to me they aren't releasing DCT first in a ZR1 model (maybe Z06) and then bringing to the base car (to control the release and manage development/advancement more). Going back to my earlier point, the more testing vehicles and the more test drivers, the quicker they can fix issues, but if they have tens of thousands of cars and drivers, and things go sideways, it will blow up. GM's nuts are WAY out on the chopping block with this car, and that trans could make or break it.
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Old 07-11-2019, 10:47 AM
  #63  
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BMW F10 M5 2016 >> DCT
BMW F90 M5 2019 >> ZF automatic 8 speed
Iím wondering why BMW stopped using DCT in M cars!
I had the chance to drive the new M5 and I am very impressed
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Old 07-11-2019, 11:01 AM
  #64  
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Originally Posted by Iker View Post
BMW F10 M5 2016 >> DCT
BMW F90 M5 2019 >> ZF automatic 8 speed
Iím wondering why BMW stopped using DCT in M cars!
I had the chance to drive the new M5 and I am very impressed
DCTs generate lots of owner complaints and service appointments. The average car buyer will feel the quirkiness of them and schedule service appointments. We had my wifeís Audi DCT into service several times, all times were told the things we observed were normal. She is back in a ZF auto BMW and life is good again. No more Audi DCTs for us.

Last edited by NY09C6; 07-11-2019 at 11:02 AM.
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Old 07-11-2019, 11:02 AM
  #65  
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Originally Posted by vndkshn View Post
I'm really surprised they are betting everything on DCT. With as much change as this car will represent, I'm really surprised they are going this far.
I guess they would have needed to change the architecture of an existing automatic or manual anyway to make it work with a mid-engine, so they just decided to start over with with the type of transmission the automotive journalists keep raving about?
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Old 07-11-2019, 11:07 AM
  #66  
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Originally Posted by vndkshn View Post
So GM can take a transmission that was designed for a ME car (making it a transaxle) and shove it into... oh, let's say a front wheel drive car like the (which is most of what they make other than trucks, Camaro, and Corvette). With ZERO changes (changes that would make it a different transmission, which was NY09C6's point). "Economies of scale" work when there are no changes.
I'm not sure you actually understand what "economies of scale" means, but you're fairly incorrect with that statement. Were that the case: see the truck engines and Corvette. Zero changes between those two sets of engines? Uhhh...

We also don't know the specifics of the transmission yet, only rumors about it. It could end up being very easily reconfigured for a different mounting and engine layout. You're assuming way too much.

what sense does it make to put a transmission that was developed for that into a car with half the power? It makes zero sense and it is something GM has never done for logical reasons.
I'd agree with that if GM's only performance car was the Corvette. But as it turns out: it's not. They have the Camaro and the CTS(-V, etc) from Cadillac. Further, there's no reason they can't alter the transmission enough to deal with less input torque or even: fewer gears! The main cost of the transmission is the R&D for it, not the actual building/assembling it. Same goes for any other part on or in the car.

On top of that, why would a truck need a DCT? GM already has a pretty awesome transmission in the trucks (their biggest advantage IMHO) and a truck doesn't really need super fast shifts because they aren't sports cars.
Well imagine this possibility, and it's one I speculated about 5-10 years ago, right here on CF: GM ditches their planetary automatic transmissions entirely, along with the last of their remaining manual transmissions. All in favor of some form of DCT? The exception to that would be the big diesel rigs which would continue to use the Allison (not GM...) transmission. If a DCT can be snicked into "auto" mode and just driven, why not?

I also think DCTs are a nitch solution and as TC autos continue to iadvance, DCTs may go away. The comments from the Aston Martin CEO make alot of sense when you think about it.
I suspect GM is seeing other directions; Aston's CEO's opinion on the direction of the auto industry isn't really a big deal. ;-)
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Old 07-11-2019, 11:09 AM
  #67  
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Originally Posted by Iker View Post
BMW F10 M5 2016 >> DCT
BMW F90 M5 2019 >> ZF automatic 8 speed
I’m wondering why BMW stopped using DCT in M cars!
I had the chance to drive the new M5 and I am very impressed
They haven't. The DCT is still an option on the M4 and the M2 competition at least. There may be one or two others.

Last edited by ByByBMW; 07-11-2019 at 11:12 AM.
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Old 07-11-2019, 11:20 AM
  #68  
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Originally Posted by Warp Factor View Post
I guess they would have needed to change the architecture of an existing automatic or manual anyway to make it work with a mid-engine, so they just decided to start over with with the type of transmission the automotive journalists keep raving about?
I completely agree. It's obvious they needed to make huge changes to accommodate the ME layout, and they are definitely trying to hit that niche. It's just a huge risk if that software isn't right (not a sports car, but see Focus, it's number 1 problem is the programing).
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Old 07-11-2019, 11:32 AM
  #69  
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Originally Posted by jvp View Post
I'm not sure you actually understand what "economies of scale" means, but you're fairly incorrect with that statement. Were that the case: see the truck engines and Corvette. Zero changes between those two sets of engines? Uhhh...
You are comparing a vehicle (Corvette) that sells what, 20-30 units a year with a truck that sells over 400k units (combining all models including GMC). So yes.. "economies of scale" applies to the engines, especially when factoring in the truck side. And don't forget Camaro in that math, since it shares the Corvette (not truck) engine.

Originally Posted by jvp View Post
We also don't know the specifics of the transmission yet, only rumors about it. It could end up being very easily reconfigured for a different mounting and engine layout. You're assuming way too much.
Heavy irony.

Originally Posted by jvp View Post
I'd agree with that if GM's only performance car was the Corvette. But as it turns out: it's not. They have the Camaro and the CTS(-V, etc) from Cadillac. Further, there's no reason they can't alter the transmission enough to deal with less input torque or even: fewer gears! The main cost of the transmission is the R&D for it, not the actual building/assembling it. Same goes for any other part on or in the car.
But that tosses :"economies of scale" out the window. When you start altering the transmission that much, you start to lose alot of the sharing of parts. Plus, it's another transmission to train on, stock parts for, etc.

Case in point, back in the days (at least late 80s early 90s), if you needed a distributor cap for your mid 70s Corvette and went to the dealer, it had one part number. The EXACT same part for a BBC was a different part number, but they were interchangeable. They may have finally changed that, but I distinctly remember that because I always laughed about it.

Originally Posted by jvp View Post
Well imagine this possibility, and it's one I speculated about 5-10 years ago, right here on CF: GM ditches their planetary automatic transmissions entirely, along with the last of their remaining manual transmissions. All in favor of some form of DCT? The exception to that would be the big diesel rigs which would continue to use the Allison (not GM...) transmission. If a DCT can be snicked into "auto" mode and just driven, why not?
Possible, and Ford definitely tried it. Didn't work out well for them. And while you might ignore the comments from the Aston CEO, you can't ignore the facts behind it. The ZF8 is a prime example of an automatic that is approaching DCT levels of performance (and outperforming some of them).
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Old 07-11-2019, 12:11 PM
  #70  
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Originally Posted by 16/C7Z View Post
This car is the biggest gamble gm will make in my lifetime.

So many things that will inherently have an issue or 2 (or 10) and this can all go sideways fast.

That's why the safe(r) approach would have been to make the ME with a conventional trans and a manual then offer the DCT and a manual over time. Just my opinion.

It seems like they are sticking to ohv engine for now. And it makes me wonder how they have this much faith in the DCT. I hope they're right as I may... be looking at the late Z06 version once I'm convinced this isn't 1984 all over again. Where every year for the next 12....they made the car better and whichever bought the year before got screwed. If they can put a car together that can make it 3 or 4yrs without huge improvements I will feel a lot more comfortable trying out an ME car..

Just tough watching the latter years if each design be night and day better then having to trade up.. in gonna try patience this time lol
On your manual observation, I agree, but I think there is a good reason why they cannot at this point in time. I don't think it's because of decreasing manual demand, because 23% manual sales (C7 number) is sizable at Corvette volumes.

I think it is because there is not currently a manual transaxle that can safely handle LT1/2 torque. It is my hope they will ultimately find a solution for later MYs.

Last edited by Foosh; 07-11-2019 at 12:12 PM.
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Old 07-11-2019, 12:23 PM
  #71  
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Originally Posted by vndkshn View Post
You are comparing a vehicle (Corvette) that sells what, 20-30 units a year with a truck that sells over 400k units (combining all models including GMC). So yes.. "economies of scale" applies to the engines, especially when factoring in the truck side. And don't forget Camaro in that math, since it shares the Corvette (not truck) engine.
But... the truck engines get changed quite a bit before being plopped into the Corvette and Camaro. And yet the economies of scale still work there, according to you.

Heavy irony.
Not really. I've clearly called out that I'm speculating. You're speaking as if it's fact. Keep swinging.

But that tosses :"economies of scale" out the window. When you start altering the transmission that much, you start to lose alot of the sharing of parts. Plus, it's another transmission to train on, stock parts for, etc.
Again: not really. The cost of the transmission is the R&D, not the building/assembly of it. That R&D can easily be paid for across multiple car lines, even if the exact DCT parts don't get put into each car.

Case in point, back in the days (at least late 80s early 90s), if you needed a distributor cap for your mid 70s Corvette and went to the dealer, it had one part number. The EXACT same part for a BBC was a different part number, but they were interchangeable. They may have finally changed that, but I distinctly remember that because I always laughed about it.
That has.... what to do with this conversation, exactly?
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Old 07-11-2019, 01:26 PM
  #72  
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Originally Posted by ByByBMW View Post
They haven't. The DCT is still an option on the M4 and the M2 competition at least. There may be one or two others.
Because its concept of design is similar to the old M5
the new M4 will be revealed next year with the same design concept of the new M5 and absolutely with ZF automatic transmission 8 speed.
Actually I can tell you the performance of the new M5 is something I couldnít believe! upshift or downshift are both fast as hell!

Last edited by Iker; 07-11-2019 at 01:28 PM.
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Old 07-11-2019, 01:37 PM
  #73  
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Originally Posted by Iker View Post
BMW F10 M5 2016 >> DCT
BMW F90 M5 2019 >> ZF automatic 8 speed
I’m wondering why BMW stopped using DCT in M cars!
I had the chance to drive the new M5 and I am very impressed
It is as simple as cost. They are going to use the same 8-speed across all M vehicles. G8x M3/M4 will be getting the same transmission.

DCT are still superior in performance application, hence all high end sports cars use DCT. I had a F10 M5 with DCT and have driven the new M5. The 8speed to me feels slower(particularly downshifts), it just didn’t feel as crisp. But 8speed Auto is more smooth day to day driving. I would still prefer DCT in my sports cars.

The complaints about DCT come from normies who treat them like traditional automatics driving them in auto mode daily.

Last edited by blipit_; 07-11-2019 at 01:41 PM.
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Old 07-11-2019, 01:54 PM
  #74  
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Originally Posted by Iker View Post
BMW F10 M5 2016 >> DCT
BMW F90 M5 2019 >> ZF automatic 8 speed
I’m wondering why BMW stopped using DCT in M cars!
I had the chance to drive the new M5 and I am very impressed
They are saying they have the 8ZF to the point where it will preform-with/out-perform? the 7DCT. FWIW my BMW 7DCT was quicker shifting the my BMW 8ZF is, but a lot is in the programing.

So far most all the new M cars are running the 8ZF as the generations change. The 6MT is also going away on most except M2, M3, M4 which so far also have the 7DCT

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Old 07-11-2019, 02:12 PM
  #75  
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Here's hoping that the transmission works flawlessly out of the gate but these things are so complex that I think it may take a bit to perfect. Software updates can definitely be an inconvenience but at least the dealer is not disassembling the car in order to implement them. Have not had my Armada's transmission updated yet but I hear it is a 3 hour service appointment.
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Old 07-11-2019, 02:16 PM
  #76  
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Originally Posted by jvp View Post
But... the truck engines get changed quite a bit before being plopped into the Corvette and Camaro. And yet the economies of scale still work there, according to you.
At this point, I think you are being intentionally obtuse.
You used the engine example as proof of economies of scale, not me. I have no idea how many parts are or are not shared between the truck and Corvette if any. They could be completely unrelated and only share displacement. I pointed out the Camaro uses the same engine as the Corvette, not the truck.
Originally Posted by jvp View Post
Not really. I've clearly called out that I'm speculating. You're speaking as if it's fact. Keep swinging.
You are assuming that it would be little to no change to use this transaxle in another vehicle and that would result in economies of scale. Keep swinging.
Originally Posted by jvp View Post
Again: not really. The cost of the transmission is the R&D, not the building/assembly of it. That R&D can easily be paid for across multiple car lines, even if the exact DCT parts don't get put into each car.
So no R&D to change the trans (as you mentioned, different case, possibly different number of gears, possibly different ratios, different programing, the list goes on an on) for a different vehicle? Interesting.

Originally Posted by jvp View Post
That has.... what to do with this conversation, exactly?
It was an example of how GM has screwed up the scale concept before. There are several others.
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Old 07-11-2019, 02:17 PM
  #77  
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Originally Posted by Michael A View Post
I have to say I am not impressed with all the tailpipe firecracker theatrics of some of today's cars. Jaguar is big into this. In an F Type R in sport mode, don't let off the gas near a cop, or he/she may open fire and ask questions later. Porsche started doing this nonsense with the 718 Cayman, to cover up the lame four cylinder sound. The whole thing comes off very fake to me, and it is fake. These cars don't have carburetors. It ranks right up there with piping in pseudo exhaust sound through the stereo (are you listening BMW). Besides if you are going to have a fireworks show coming out the exhaust, activate all the senses, and do it right with flames coming out the exhaust. For those of us not into creating a sideshow, there should be a setting in the car to selectively turn all this nonsense off.
It comes off as fake because it is fake. Porsche and others try to replicate the exhaust sounds of a racing exhaust. So they have the computer inject a few drops of gas over the exhaust under specific conditions to get the popping sound. In order to maximize performance at redline, where race cars live, a racing cam has a significant amount of overlap between the exhaust and intake valve openings. thereby maximizing intake valve duration. The first production car that I had with a racing cam was a 1968 Z28. Two telltale signs of a racing cam: engine lopping and popping sounds made by unburnt fuel in the exhaust at low RPM. In the last Petite LeMans race I attended in Baltimore, you could see exhaust flames and hear the popping as the cars slowed for a hairpin.
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Old 07-11-2019, 02:27 PM
  #78  
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Originally Posted by blipit_ View Post
It is as simple as cost. They are going to use the same 8-speed across all M vehicles. G8x M3/M4 will be getting the same transmission.
Originally Posted by BEAR-AvHistory View Post
They are saying they have the 8ZF to the point where it will preform-with/out-perform? the 7DCT. FWIW my BMW 7DCT was quicker shifting the my BMW 8ZF is, but a lot is in the programing.

So far most all the new M cars are running the 8ZF as the generations change. The 6MT is also going away on most except M2, M3, M4 which so far also have the 7DCT
I think fewer and fewer BMW drivers want to drive manuals at all. I'm an instructor for BMWCCA and I don't see many new generations of BMWs at the events, even M cars. With technologies like autonomous driving becoming in demand features, if people are too lazy to drive their car, they are definitely too lazy to shift for themselves, even with paddles.

But as pointed out, it's all down to the programing. That alone makes or breaks the experience. I'd even venture the guess that the R&D costs are largely due to programing, one program won't work for every single vehicle out there, which is why the same transmission in different models/brands/etc of cars result in completely different experiences/opinions.
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Old 07-11-2019, 07:02 PM
  #79  
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As I’ve said in other posts, I’ve driven quite a few high performance DCTs over the years. Most of the time they are an absolute joy to drive, even if you love manuals as I do.

So, the only real question for me pertains to the quality and tuning of the C8 DCT. The ones I’ve heard shifting, especially on tracks, leave an impression of very high quality and very fast, almost instantaneous power shifts. If the DCTs in the retail base C8s are of the same quality and have the same tuning I think Corvette is going to have a lot of very happy campers even if there is no manual. But, if the base C8 DCT is of a lower quality and/or tune than those track cars, I think Corvette is going to have some problems with sales numbers.

Bottom line, if it shifts close to those track cars, we will likely buy a C8. But, if it shifts like the C7 A8 there will simply be no C8 in our future.
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Old 07-11-2019, 10:23 PM
  #80  
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Originally Posted by B747VET View Post
As Iíve said in other posts, Iíve driven quite a few high performance DCTs over the years. Most of the time they are an absolute joy to drive, even if you love manuals as I do.

So, the only real question for me pertains to the quality and tuning of the C8 DCT. The ones Iíve heard shifting, especially on tracks, leave an impression of very high quality and very fast, almost instantaneous power shifts. If the DCTs in the retail base C8s are of the same quality and have the same tuning I think Corvette is going to have a lot of very happy campers even if there is no manual. But, if the base C8 DCT is of a lower quality and/or tune than those track cars, I think Corvette is going to have some problems with sales numbers.

Bottom line, if it shifts close to those track cars, we will likely buy a C8. But, if it shifts like the C7 A8 there will simply be no C8 in our future.
I suspect that the C8's DCT will be quite similar to PDK, which offers manual shifting, automatic mode, and Sport or Sport Plus modes. Moreover, the latest generation PDK transmissions incorporate new fuel-saving modes which decouples the transmission from the engine to allow the engine to idle while coasting. So the C8 driver will likely have several options as to how he wants the DCT to shift.
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