AORoads

^^^ Yes, I think we've seen some with 10K miles or more that had issues, but not much more. Then again, there aren't a whole lot of cars yet on the road with 30K + of C8s. Only read of a few, may be more tho.

Phil1098

That would explain his view. If mine shot craps at 89 miles, I'd be a bit surly too.

TrojanWarrior

Its not a $100,000 car. Its a car. that has the same transmission/power train at its starting price in the mid $60's. Adding on a bunch of creature comforts, as well as an HTC, drives the price up but, again, just because maybe that's what you paid, doesn't make it a $100,000 car.

To be clear, the problem is unacceptable and should not exist after 5+ years of production regardless of the price.

DerbyCity

What is the problem with the transmission? I had heard early on that it was failure to remove material left behind in the manufacturing and it was plugging ports. What is failing?

Phil1098

Am I supposed to apologize for stating what the Corvette tech that I've known for 40 years told me? I asked him specifically how many he has had to change out on C8s and he said zero. Almost every time I walk in the shop he's changing a transmission in something, just not a C8. I know of three of the GM 9 speeds in the new Blazer that have **** the bed. I have two friends that own the new Blazer, one has transmission issues, and the other one had a catastrophic failure.

Phil1098

Honestly, I think it's more that GM is trying to get their arms around issues they've had. ANY new major component has the SOP of dealer not allowed to open, crate and replace is all the dealers are allowed to do. As time goes on there will be dealer training and like any other transmission they'll be allowed to open it to see what's wrong. I have yet to hear of a serious failure, I.E. stripped splines, bent shift forks, exploded clutches, etc., it's still control related with sensors and solenoids. That doesn't taste any better to the customers that "need" a new DCT, but it's how it is right now.

Dave O

I've had to have my valve body replaced twice, and was told that I am the only one (at my dealership) that has had to have theirs replaced twice. Both times they tried the flush first but did not correct the problem. And both times I was in and out fairly quickly, not much more than an oil change so a minimal inconvenience on my part.

At my dealer of preference, they have some of the best techs in California. They have a tremendous reputation as corvette specialists and the GM of the dealership is an avid corvette enthusiast and races them from time to time. I was told by the GM and the tech that the sensors and solenoids in the valve bodies have very small passage ways, easily prone to plugging by the smallest of particulates. I don't know if this debris is from the manufacturing process or from the clutches wearing in and shedding debris. Regardless, in my opinion, this is the cause of the majority of issues with the DCT. But this is just my opinion, and I could be wrong. My dealership has also said that they haven't had a large failure rate on the DCT, and I believe have only actually replaced one or two of them. My hope is that GM/Tremec is learning from this and will update the valve bodies in the future to be less prone to plugging.

Greg00Coupe

Dave O. Sounds like you got a great dealer! Why not name them please? Folks might appreciate a great tip!

DerbyCity

David, thank you for your reply. Do you know if I will have a repaired DCT put into my Vette?

Dave O

Abel Chevrolet in Rio Vista. Their GM is a forum member (RichieRichZ06) and supporting vendor.

Dave O

I have no idea. But others have reported that when they replace a DCT it is a new one, not a rebuilt one.

bmanahan

No way it is that small. That would be only 3 cars per year with a transmission issue. My dealer had several Corvettes backed up before me with DCT issues.

psmithzr1

Just providing some data on my Z06 DCT failure in case you haven't seen my other posts.
Leaking oil from the DCT from day one. Noticed the puddle on the floor in the garage after 69 miles.
Removing the aluminum shear plate revealed oil coming from the driver-side half-shaft DCT seal.
Dealer shop foreman said he could move the half-shaft up and down allowing oil to run out.
Looks like a bad bearing to me but maybe more complicated than that.
I did see some smoke coming from the engine in the rearview mirror when stopped in traffic.
Waiting for over 2 weeks for new DCT but no ETA from GM.
It sucks being the 1 in 100 or 10,000 that fails.

Sportsman2003

There were talks on here at some point stating GM was putting reman units in warranty cars.

JToddH

Curious if your dealer sold one of the 100 or so C8’s sent to Michigan? (One source suggested it was trans issues)

Phil1098

That I do not know, I don't talk to the sales department too much anymore, the manager that took care of Corvettes took another position in the company.

DerbyCity

I had concerns about this and thought that it was corrected by now ( April 2023 ) Never would have thought that I would be one in 10,000 (;
This Wednesday it will be three weeks without an estimated replacement.

ArizonaZ06

New 2024 DCT oil pan is the, "only change".

Obviously now in production year 5 there is no a transmission issue to fix.

Crossofiron

Nuff said.

DerbyCity

Didn’t the fill plug move to be more accessible?