I am also watching this very closely, as I have an order waiting for an allocation (likely will be a '23 model year Stingray). I have read in a few C8 Facebook groups that some '22 owners have experienced the issues where they lose some of the gears. Hard to put context around it in terms of failure rate, but reading threads like this person posted doesn't inspire confidence. That said, it appears the leaking issue would be less likely to occur, based on the pan change.

Those '22 model year failures I read about were within several hundred miles. These failures, along with having to wait many weeks in some cases for replacements to be installed, also is disheartening. I try to remember this is a "first world problem" in the grand scheme of things though.

I appreciate all the responses in this thread just like the OP.

 

I'm not too worried about it. Subaru forums were saying the same thing about the CVT ten years ago and my Legacy is 135k miles strong.

 

No offense, sir, but the last place I would expect to find credible evidence about anything is Facebook.

Ray

 

You want to raise awareness?

Get every owner victimized by a lemon DCT to join you in a class action lawsuit against Chevrolet, Tremec, and GM. It will be summarily dismissed since when you bought the car and signed the sales documents ― which neither you nor anyone else ever reads ― compels you to settle disputes by binding arbitration. And guess who gets to pick the arbitrator? You guessed it; GM. And guess how the arbitration will conclude? That's right, GM will repair or replace at their discretion any defective parts with new or refurbished parts. End of story. Case dismissed.

You will get on TV for 10 minutes. Maybe even cable. And you will embarrass GM. And you may cost them a sale or two. But even after everyone is made aware, what do you expect to happen?

If you endeavor to do this and have credible evidence to support your claim, I will donate to your legal fund. Hell, maybe Chevy sold a bum DCT to an attorney and he or she will take the case pro bono!

I love the post from the guy who gets his information from Facebook. According to reliable sources ― insert facetious grin here ― on Facebook, the C8 DCT "loses gears". No further exposition on what exactly "losing gears" means ― do they fall out, lose their teeth, refuse to mesh? ― but hey, he's on the list for a 2023 (really?) and he's concerned.

Ray

 

There hasn't been one DCT that has "lost gears", none. Has there been some that the controls failed to operate, yeah, but there hasn't been any catastrophic failures. So when GM puts in a valve body do all the "lost gears" magically heal themselves? That in and of itself is proof that the gears, synchros, shift forks, and shafts don't have any issue. It's a manual transmission that has computer controlled shifting. Computers are fast, but they can't move things, that's why solenoids are used and if one gets stuck due to debris, it won't shift. Doesn't mean the whole transmission failed because it didn't.

 

Here is the California license plate I'm transferring from my F430 to my C8. The C8 DCT is more "F1" than the Magneti-Marelli box in the 430 so I figured it would be apropos ...

 

My car has only 700 miles on it but so far the transmission has been flawless. Much better than the 2020 although the 2020 did have some early issues and threw a code once or twice it never needed service. It just seemed to fix itself after awhile.

 

To simply ansswer your original questions, yes there have been owners on this forum with '22s who have experienced transmission issues & transmission replacements. Their posts can be found through the search feature.


Car-specific FB groups are no less credible than this forum, or other similar forums. There may actually be more owners in FB groups than this forum which would then provide a larger data sample.

 

I agree with you, once I added the 2 extra quarts it was quieter, I thought it was just me but glad someone else had the same experience.

 

I have never heard of a C8 having a DCT self destruct, gears destroyed, holes knocked through casing, etc etc. I have heard a couple cases where the there was a problem with the rail that the shift forks ride on and supposedly the alignment and setup of some of these parts can only be done at the factory and not by any GM field service techs. Seems to be very rare though.
More common issues appear to fall into a couple different categories, that might be interrelated or confused because we don't know the ultimate truth in these cases, only anecdotal evidence:
1) Contamination issue with solenoids, valve bodies, etc.
2) Clutch failure (might be related to #1)
3) mLSD/eLSD whine / shimming problems
4) Porosity issues
5) TCM / electrical / sensor problems
6) Pan cover / gasket leaks, cracked casing around PAN and DCT filter covers (due to overtorque of pan cover bolts). This problem may be related to #4 above, but techs failed to determine the correct source of leak, then over torqued the cover bolts (they are low low torque).
7) Snapped half-shafts (not really a DCT issue, but a drive train issue and also shows how stout the DCT really is)

 

Not from any verifiable source. It may be speculated, but not one DCT has been pulled apart by anyone other than someone inside GM and or Tremec, and they sure as hell aren't posting that info.

 

Ahhhhh he knows about FSCs. Tell me have you ever handled a class action with a FSC? I have never seen that done. Just so you know also, when ever I sign something and I read clauses I do not like or agree with but I know I have no choice, I circle that specific clause and write next to it "Contract of adhesion, not voluntarily agreed to." I could not tell you if it is necessary as I usually work things out lol.

Tell me though, without those voicing the issues that you of course do not think exist, how would I find these class members? I would not pay for mail sir and I sure as hell would not do anything for free...you see I already did my pro bono in law school.

You may be on to something though, I give you that.

 

As I said, I haven't heard anything other than speculation on the shift forks / rails. However I would give some of the posts a little more credit than others, like the one I read from someone at Dodson about what they saw as a potential cause for the problem with the shift fork alignment:
https://www.corvetteforum.com/forums...post1602044863

It would be nice to see a detailed video of the internals of the TD9080, but I haven't seen one yet. I did capture some facebook videos that a corvette tech at a dealer posted as he was tearing one down. He showed some issues with solenoids, a wiring harness issue, and an o-ring issue with the pipe/tube that connects to the top of the external DCT filter, also talked about the really low torque specs and that some people may be over torqueing bolts on covers. I was surprised to see in that video a lot of ZIP TIES being used for cable management. Given the potential for heat, slippery DCTF fluid etc, I would be a lot more comfortable with a safety wire approach vs plastic ties.

Here is this nice video of the TR9070 used in the Mustang:

Much different transmission, but a DCT nonetheless and it appears there are some similar design elements in play, especially the synchronizers and shift forks.
Solenoids and valve bodies are moved around because they needed to flatten the TR9080 to get center of mass lower, and the TR9080 has two output shafts and diff's integral to the design.

 

Here's an idea, find a totally trashed C8 on CoPart. Pull the DCT out and do a whole series of technical deep dive videos on the DCT internals.
I know GM has a nice cutaway model on display, but I would like to see one actually fully disassembled and every part scrutinized.
It would be awesome too to see videos of the manufacturing process for all the parts, including castings, gears, etc. Do they shot peen all the gears in the TR9080, etc.

 

I read the DCT threads for months before I picked up my 21 HTC - both here and on FB C8 groups. @JABCAT has a point about FB C8 groups having more owners than there are on here. I saw a poll several months ago on one of the FB C8 pages asking if any owner had any type of problem with their DCT and the last time I looked at it there were well over 2000 responses. When you did the math it was a little under 2% - and this included owners who reported their DCT threw a code and after they drove it a couple of more times the code went away and hadn't come back.

I decided to look at this car the same way I look at anything - if it's mechanical it can fail.

 

I'd disagree with the statement about owners sharing their experiences in a group, regardless of its reputation. Just like any social media platform (this one included), people can ramp up the extent of their issues, but I believe the people posting that are looking for the same help and assurances that the OP here is doing. Again, I appreciate the level of detail that is provided here, but I won't discount other C8 owners reporting the same symptoms on their 2022 models just as been done here. The situation with this transmission is enough to give me pause with a purchase given the cost of the part itself.

 

Before you summarily dismiss what I have to say by referencing the use of a platform that you might not like, I did not specify exactly what the failure was because I was using general terms. Just like others on this forum have reported with failures, one of the '22 owners was unable to shift to either the odd- or even-numbered gears after he began getting error lights about his transmission. Furthermore, I am actually on the list for a '22 but because of the current allocation situation at the dealership, I probably will have to reorder it as a '23.

Just like the originator of the thread, I am here to learn and I appreciate when other people provide the detailed information they do. As others have mentioned, there is a larger sample size on the FB groups, so that's why I review them.

 

A very balanced way to look at it.

 

I apologize for the use of a non-specific term ("lost gears"). It was the loss of function because of the inability to shift, not a metal failure.

 

No need to apologize, it's all good. I just wanted to be clear the TR9080 isn't fragile, I also won't say it's perfect (mine is leaking out in the garage right now).