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Old Aug 31, 2025 | 11:25 PM
  #561  
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Originally Posted by DeltaT
Manual transmission, think of trying a downshift to 4th and hitting 2nd instead . It's often called mechanical over-rev.
How do you do that with an LT6 that's only in a Z06 and only comes with an automatic. I believe even paddle shifting in manual mode the computer will prevent over rev.
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Old Sep 1, 2025 | 12:04 AM
  #562  
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Talking in general. In this instance they were talking about the LS7. I don't believe the Z06 will let you get into that, except maybe in some weird spin where you ended up going backwards, dunno.
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Old Sep 1, 2025 | 06:53 AM
  #563  
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Originally Posted by DeltaT
Manual transmission, think of trying a downshift to 4th and hitting 2nd instead . It's often called mechanical over-rev.
Thank you.. Was wanting to see how the logic is programmed on these as compared to our bikes(Ninja's)
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Old Sep 1, 2025 | 07:34 AM
  #564  
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Originally Posted by cajunboyz
Thank you.. Was wanting to see how the logic is programmed on these as compared to our bikes(Ninja's)
Except if the call for the downshift in manual mode would place the car in an over rev, it will not accept the order. It will only downshift to the lowest gear that will not over rev. It's all computer controlled, the Kawasaki is foot controlled with a rotating shift drum turned by a ratcheting arm attached to the shifter.
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Old Sep 3, 2025 | 03:34 PM
  #565  
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Originally Posted by DeltaT
Talking in general. In this instance they were talking about the LS7. I don't believe the Z06 will let you get into that, except maybe in some weird spin where you ended up going backwards, dunno.
Yes, was refering to C8 ZO6, Thank You
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Old Sep 21, 2025 | 01:58 PM
  #566  
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Originally Posted by smithers
Just came across this video on youtube. LT6 seized up at 621 miles. Not a ton of info. Owner basically says he did a proper break in. They were doing a little pull (its in the video, nothing crazy) and the engine started knocking and seized. City Chevy had a new engine in the car in about 2 weeks. GM didn't let the dealer open up the engine, I assume they had to ship it back to GM intact for some analysis.

Owner of the car says he knows of 3 engine failures. The one that died at like 50 miles that we all heard about, one other one, and his. So with about 1000 cars built, 3 engine failures. So about a 0.3% failure rate so far.

https://www.youtube.com/watch?v=eCfS12zAEKQ

Why would you care about how many other owners have had this problem? I've had similar issues in the past and I've never asked about or inquired about other instances! I focus on dealing with my business not others. What was your motivation for digging into other owners problems?
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Old Sep 21, 2025 | 03:10 PM
  #567  
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Originally Posted by Brian Ritter
Why would you care about how many other owners have had this problem? I've had similar issues in the past and I've never asked about or inquired about other instances! I focus on dealing with my business not others. What was your motivation for digging into other owners problems?
Where do you get the idea that I was digging into other peoples problems by sharing a video that the owner put on social media that just happened to show up in my youtube feed years ago? lol

This really isn't that big of a deal. Some early cars blew up, there were concerns on the forum about it all those years ago when it happened. The world has moved on, but the post remains as the mods merged all the engine failure threads into a post I made and it somehow became this stickied topic. I can't change it. I hope your day gets better.
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Old Sep 21, 2025 | 10:42 PM
  #568  
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Are you having a bad day?

This is a forum not a inquiry into ones social security number or their net worth.

Hope you have a better day tomorrow!

Originally Posted by Brian Ritter
Why would you care about how many other owners have had this problem? I've had similar issues in the past and I've never asked about or inquired about other instances! I focus on dealing with my business not others. What was your motivation for digging into other owners problems?

Last edited by Mark2021C8; Sep 21, 2025 at 10:48 PM.
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Old Sep 22, 2025 | 06:47 AM
  #569  
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I think its time to make this thread a "C8 Z06 Problems" sticky like in the C8 General section, since LT6 failures are virtually non-existent at this point.

Mods, what say you?
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Old Sep 24, 2025 | 10:33 AM
  #570  
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I had a failure in my Zo6 Z07 used primarily as a track car. It had 45 track days on it and about 8000 miles. It’s in the shop now. When I came off the track, I had the engine running as I was reviewing a video. The car began surging, and indicated random misfires. At the dealer they could replicate this behavior. It would start and run fine for a few minutes and then start surging. If you turned it off and right back on, it initially sounded ok, but again after a few minutes the process would repeat. They traced it to a bad third cylinder. Boroscope showed severe damage to the cylinder but GM wasn’t convinced it needed a new engine. The engine is now dropped and I’m waiting for follow up, but they said there are no engines available. I’m not all that upset, bout the engine going because I do track it a lot and it’s a high strung beast. I did blow 2 engines on my c8 stingray that were replaced. And if you’re wondering about the break in, believe me it was babied for 1500 miles. In fact the car never had even one launch control, as I could care less about 0-to times.
I am however annoyed about other problems I have experienced, including a failed starter and a failed alternator, as well as a seized rear parking brake. When, the starter and alternator went, the car basically shut down, and I couldn’t shift out of park. There was no indication of the alternator going.
Hooefully GM will approve the warranty for a new engine, and one will be available soon. I have lost too many track days this year.
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Old Sep 24, 2025 | 12:29 PM
  #571  
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bobgolub,

In regards to your "failed starter" what happened?

I had a heat soaked starter that failed at Road Atlanta after a full track day at the RA gas pumps with melted wiring harness near the starter. GM replaced under warranty but I must have been one of the first because it took GM Tech Center engineers about a month to finally come up with a solution well over a year ago. After my diagnosis I know of two other track rats that were diagnosed with heat soaked starters that failed and replaced within a week.





Originally Posted by bobgolub@hotmail.com
I had a failure in my Zo6 Z07 used primarily as a track car. It had 45 track days on it and about 8000 miles. It’s in the shop now. When I came off the track, I had the engine running as I was reviewing a video. The car began surging, and indicated random misfires. At the dealer they could replicate this behavior. It would start and run fine for a few minutes and then start surging. If you turned it off and right back on, it initially sounded ok, but again after a few minutes the process would repeat. They traced it to a bad third cylinder. Boroscope showed severe damage to the cylinder but GM wasn’t convinced it needed a new engine. The engine is now dropped and I’m waiting for follow up, but they said there are no engines available. I’m not all that upset, bout the engine going because I do track it a lot and it’s a high strung beast. I did blow 2 engines on my c8 stingray that were replaced. And if you’re wondering about the break in, believe me it was babied for 1500 miles. In fact the car never had even one launch control, as I could care less about 0-to times.
I am however annoyed about other problems I have experienced, including a failed starter and a failed alternator, as well as a seized rear parking brake. When, the starter and alternator went, the car basically shut down, and I couldn’t shift out of park. There was no indication of the alternator going.
Hooefully GM will approve the warranty for a new engine, and one will be available soon. I have lost too many track days this year.
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Old Sep 24, 2025 | 12:38 PM
  #572  
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Originally Posted by Mark2021C8
bobgolub,

In regards to your "failed starter" what happened?

I had a heat soaked starter that failed at Road Atlanta after a full track day at the RA gas pumps with melted wiring harness near the starter. GM replaced under warranty but I must have been one of the first because it took GM Tech Center engineers about a month to finally come up with a solution well over a year ago. After my diagnosis I know of two other track rats that were diagnosed with heat soaked starters that failed and replaced within a week.
I read your post and mentioned it to the tech. He said the wiring harness looked fine. What exactly is the fix?
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Old Sep 24, 2025 | 02:23 PM
  #573  
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Originally Posted by bobgolub@hotmail.com
I had a failure in my Zo6 Z07 used primarily as a track car. It had 45 track days on it and about 8000 miles. It’s in the shop now. When I came off the track, I had the engine running as I was reviewing a video. The car began surging, and indicated random misfires. At the dealer they could replicate this behavior. It would start and run fine for a few minutes and then start surging. If you turned it off and right back on, it initially sounded ok, but again after a few minutes the process would repeat. They traced it to a bad third cylinder. Boroscope showed severe damage to the cylinder but GM wasn’t convinced it needed a new engine. The engine is now dropped and I’m waiting for follow up, but they said there are no engines available. I’m not all that upset, bout the engine going because I do track it a lot and it’s a high strung beast. I did blow 2 engines on my c8 stingray that were replaced. And if you’re wondering about the break in, believe me it was babied for 1500 miles. In fact the car never had even one launch control, as I could care less about 0-to times.
I am however annoyed about other problems I have experienced, including a failed starter and a failed alternator, as well as a seized rear parking brake. When, the starter and alternator went, the car basically shut down, and I couldn’t shift out of park. There was no indication of the alternator going.
Hooefully GM will approve the warranty for a new engine, and one will be available soon. I have lost too many track days this year.
I think you will find, for the most part, that the original intentions of these threads are good. But they quickly go off the rails. And then money steps in and shuts them down. Whether it be sponsors, manufacturer, owners who don't want to hear about issues or just dumb luck. It went that way with the LS7 valve guides, the LS6 valve springs, the lt4 heat soak on track and it will go that way for any issues here. Problems hurt sales and cost people money.
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Old Sep 24, 2025 | 02:29 PM
  #574  
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They replaced the starter and the complete wiring harness from front to back of the car. Of course it fixed the problem at the time but since I have three C8 Z06s that I exclusively track I am wondering when the next time I will have the issue as it is fixed but I don't think the root cause has been fixed on any C8 Z06s that are tracked with significant heat where the starter is located.

Originally Posted by bobgolub@hotmail.com
I read your post and mentioned it to the tech. He said the wiring harness looked fine. What exactly is the fix?
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Old Dec 16, 2025 | 05:22 PM
  #575  
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Originally Posted by cajunboyz
Thank you.. Was wanting to see how the logic is programmed on these as compared to our bikes(Ninja's)
C8 with Manual Transmission-no su h thing
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Old Dec 19, 2025 | 09:55 AM
  #576  
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Originally Posted by Amoreloba
Knock knock
Who's there
Cylinder 1 3 5 7
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Why do people have to act like they are funny? FSM!!!
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Old Dec 19, 2025 | 09:57 AM
  #577  
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Originally Posted by Mark2021C8
They replaced the starter and the complete wiring harness from front to back of the car. Of course it fixed the problem at the time but since I have three C8 Z06s that I exclusively track I am wondering when the next time I will have the issue as it is fixed but I don't think the root cause has been fixed on any C8 Z06s that are tracked with significant heat where the starter is located.
Just wondering, why do you have three copies of the same car?
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Old Dec 21, 2025 | 12:24 PM
  #578  
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Originally Posted by Spacewalker
I think you will find, for the most part, that the original intentions of these threads are good. But they quickly go off the rails. And then money steps in and shuts them down. Whether it be sponsors, manufacturer, owners who don't want to hear about issues or just dumb luck. It went that way with the LS7 valve guides, the LS6 valve springs, the lt4 heat soak on track and it will go that way for any issues here. Problems hurt sales and cost people money.
I agree, they aren't the best but the thread is better than nothing, IMO.
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Old Dec 30, 2025 | 08:19 AM
  #579  
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Unfortunately it appears my new 2026's engine can be added to the list of premature failures. Just after 480 miles it started to develop a vibration at ~2k RPM that soon worsened to full-on shaking after a few miles, with the MIL alternating between solid and flashing. Took my insurance 3 tries and almost 5 hours to get a flatbed tow that could properly handle the car, but finally dropped the car off at my dealer. It was right before their holiday closure, so it took until yesterday for them to do any diagnostics. They don't have a full analysis yet, but Chevrolet wants to do a full engine replacement. No idea on an ETA.



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Old Dec 30, 2025 | 08:40 AM
  #580  
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Sorry to hear about your problem. I was thinking with the beginning of MY 2026, GM had resolved all previous Z06 engine and transmission problems. Evidently not. Hope you get a quick and relatively painless resolution.
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