Is a dual-clutch transmission right for you?
#21
Le Mans Master
What I'd like to know (and what I might be concerned about) is the expired-warranty cost to replace parts of a DCT. I don't see much mention of that, possibly because most people who own them either don't keep it past a warranty, or keep the car but use it very little. I used to know the costs to rebuild, maintain and even purchase a new 4A, 5A, and 6A, but I've left that info untouched for too many years to be current.
Anyone got any ideas on costs AFTER the warranty is off the car and DCT trans? If you want, you can take labor rates if it's a full installation, at between $100-$150/hr.
Anyone got any ideas on costs AFTER the warranty is off the car and DCT trans? If you want, you can take labor rates if it's a full installation, at between $100-$150/hr.
Last edited by NY09C6; 07-10-2019 at 04:37 PM.
#22
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#23
Racer
Just for a rough estimate I went and copied the following from a Porsche forum.
"If I am reading the parts diagram correctly, a new '09 Cayman S PDK transmission is 9G2-300-021-20 dealer list $27,264.66, a reman unit is 9G2-300-021-2X dealer list $12,125.42.
While it is correct that most service parts (and tech doc) are unavailable, you can get the valve body, cooler, seals, and a few other odds and ends. The valve body is often what needs attention."
"If I am reading the parts diagram correctly, a new '09 Cayman S PDK transmission is 9G2-300-021-20 dealer list $27,264.66, a reman unit is 9G2-300-021-2X dealer list $12,125.42.
While it is correct that most service parts (and tech doc) are unavailable, you can get the valve body, cooler, seals, and a few other odds and ends. The valve body is often what needs attention."
#25
Because I prefer an actual MT, I drove them both in "manual mode" w/ paddles all the time.
#26
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The Corvette A8 doesn't either, though it will under some circumstance.
Instead, the majority of shifts are accomplished with some combination of throttle reduction, timing retard, and clutch or torque converter slippage. Jerky shifts were considered to be an indication of high performance at one time, when cars only had around 500 horsepower, but they are horrible for traction management at higher power levels.
#27
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#28
I can't find it now, but I distinctly remember when the A8 was about to be introduced, GM published some data purporting to show the A8 to be equal or better than the PDK in terms of shift speed. Most believed it at the time, and that was one reason the auto sales percentages jumped suddenly over manual.
Fast forward to today after the A8 has created so much angst, not many accept that anymore, and so many expect just going to a DCT is going to be nirvana. I think the PDK has raised DCT expectations to mythical proportions. I hope they aren't disappointed again, but this is another of those things I'm keeping my fingers crossed about.
Fast forward to today after the A8 has created so much angst, not many accept that anymore, and so many expect just going to a DCT is going to be nirvana. I think the PDK has raised DCT expectations to mythical proportions. I hope they aren't disappointed again, but this is another of those things I'm keeping my fingers crossed about.
Last edited by Foosh; 07-10-2019 at 05:19 PM.
#30
Banned Scam/Spammer
Wow, Thank You.
Refreshing post and gotta love the posts about the "to die for", God Almighty Porsche PDK followed by a $27,000 part price for a replacement PDK in a Boxster/Cayman. The guys who memorize their car magazine articles never get the ugly side of these engineering master pieces.
Maybe the C8 could come with a option for a manual M22 Rock Crusher or an ST10 Borg. LOL!
#31
Burning Brakes
Nissan GT-R, Jerky @ Low Speeds
VW Golf GTI, FUN
BMW Z4, Perfect.
BMW M6, This was a 1st gen BMW DCT, very jerky @ low speeds and not as crisp as the Z4 I had
VW Golf GTI, FUN
BMW Z4, Perfect.
BMW M6, This was a 1st gen BMW DCT, very jerky @ low speeds and not as crisp as the Z4 I had
#32
I am distinctly familiar with the AMG GTC which has the dual clutch trans and it is amazing. Like the Porsche PDK its very fast and very easy to fall in love with. Simply put no human can shift as fast in a manual as the dual clutch can do it. If the new Corvette gets one it will likely be beneficial to the car.
Last edited by Katie22; 07-10-2019 at 06:26 PM.
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thebishman (07-11-2019)
#33
Le Mans Master
Thread Starter
DCT does not have to be in a sports car, but not sure about what GM is planning. All this talk of up to 10% better mpg makes me think a lot of mundane passenger type vehicles may get DCT.
#34
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#35
Drifting
I have had three dual clutch vehicles. The first was a DSG on a GTI, and I generally liked it. It was a little quirky especially at slow speeds it could be herky jerky, but it it was pretty flawless otherwise. The second was on a BMW 135is. I really loved that car and would still have it if it weren’t for the DCT. The only time it worked awesomely was while it was in motion. Driving in DC traffic was painful. You never knew if it was going to lurch or just sit there. I don’t know how many times I’d hit the gas only for it to coast into traffic. I took it to BMW several times but “nothing was wrong” or they “couldn’t duplicate the issue”. I currently have a Macan Turbo with PDK and have driven 911s and Caymans with PDK and they are totally awesome. So I’m hoping Chevrolet gets it right.
#36
Instructor
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golden2husky (07-12-2019)
#38
Le Mans Master
I think the smart bet is to wait and see and not be an early beta tester., errr I mean, early adopter for GM.
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vndkshn (07-11-2019)
#39
Safety Car
Random thoughts about this stuff that apply to things said above... Had the F-Type, shifts were fast but doesn't come on power as quickly as the PDK, something that only stands out when you're flogging it. Agree about the differences in tuning on the ZF gearboxes, I've had a half dozen of them and they all felt a little different.
My own opinion is that I'd like to have a manual transmission, don't give a crap if it's slower, it's more fun and I like to enjoy my cars in the real world rather than talk about numbers on the internet. If I have to choose between having moms automatic over a DCT I'd take the DCT all day every day but with one qualification: I'd much rather have that ZF out of the F-Type in lieu of a bad dual clutch. A bad DCT can be a pain, been there, sold that.
About not noticing the difference between a DCT and the torque converter autos; my daughter could notice the difference when she drove my car a few weeks ago calling it more connected and responsive when on/off the gas and shifting. She doesn't know a thing about cars, transmissions and all that fun stuff, she is 30 and driving a Santa Fe and I told her nothing but she noticed the shifting and more direct feel immediately. I have to take people at their word when they say they cant tell a difference if for no other reason than there is no point in lie lying about it. Seems strange though. I notice as soon as I push the gas pedal just from the way they drive off from a standstill.
The PDK isn't perfect, it manages a good impression of a standard TC box in auto mode but the shifting has become a little clunky in the newer 8 speeds in auto/normal from a stop because it try's to shift up too quickly to improve economy which causes you to put your foot into it harder when the acceleration falls flat which causes it to downshift from the gear that it should have never left in the first place making for a not so smooth take off. Easy enough to fix, leave it in sport or go manual and you're safe but otherwise you're going to get something less than the expected Germanic precision from it in normal. Not just me saying this, the complaint is extremely common.
The A8... Yeah, I first tasted it in the Camaro, was clearly slower power on to power on than a DCT I had at the time in an E92, I mean much much slower. The BMW could put you off the road if you weren't careful it came back on power so hard and fast after a shift. I don't care what GM said, it's not enough to just select another gear, you have to be able to get on the power. If you cant the shift is still ongoing.
My own opinion is that I'd like to have a manual transmission, don't give a crap if it's slower, it's more fun and I like to enjoy my cars in the real world rather than talk about numbers on the internet. If I have to choose between having moms automatic over a DCT I'd take the DCT all day every day but with one qualification: I'd much rather have that ZF out of the F-Type in lieu of a bad dual clutch. A bad DCT can be a pain, been there, sold that.
About not noticing the difference between a DCT and the torque converter autos; my daughter could notice the difference when she drove my car a few weeks ago calling it more connected and responsive when on/off the gas and shifting. She doesn't know a thing about cars, transmissions and all that fun stuff, she is 30 and driving a Santa Fe and I told her nothing but she noticed the shifting and more direct feel immediately. I have to take people at their word when they say they cant tell a difference if for no other reason than there is no point in lie lying about it. Seems strange though. I notice as soon as I push the gas pedal just from the way they drive off from a standstill.
The PDK isn't perfect, it manages a good impression of a standard TC box in auto mode but the shifting has become a little clunky in the newer 8 speeds in auto/normal from a stop because it try's to shift up too quickly to improve economy which causes you to put your foot into it harder when the acceleration falls flat which causes it to downshift from the gear that it should have never left in the first place making for a not so smooth take off. Easy enough to fix, leave it in sport or go manual and you're safe but otherwise you're going to get something less than the expected Germanic precision from it in normal. Not just me saying this, the complaint is extremely common.
The A8... Yeah, I first tasted it in the Camaro, was clearly slower power on to power on than a DCT I had at the time in an E92, I mean much much slower. The BMW could put you off the road if you weren't careful it came back on power so hard and fast after a shift. I don't care what GM said, it's not enough to just select another gear, you have to be able to get on the power. If you cant the shift is still ongoing.
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Michael A (07-10-2019)
#40
Melting Slicks
You don't really understand transmissions. The guts of the DCT can be put in any "case" GM wants. If GM wants to put that DCT into a FWD car, I am positive they could find a way. The transaxle in the C8 is a "configuration" of a DCT from the transmission manufacturer, such as Tremec or ZF.