[JCobalt]

I dropped my C7 off at the service dept Monday morning so they could check something out. Shifting from 1st to 2nd is really stiff and crunchy (after 900 miles) and when the clutch is disengaged it makes a loud clank. I cannot even tell you when it happened, but I can say I noticed it when the radio was off and the windows were down. I did feel the crunchy shifting before that, though, and I thought it was something I was doing incorrectly or it was normal.
So it's been there at the dealership for a few days and they're stumped. They admit something is not right, but they can't diagnose the problem. Their first step is to compare it to another 7 speed C7...but there isn't one.
I have to wait until they get one in. Does this sound like a normal process, or should it not be so difficult to identify the problem? I understand it's "all-new" but I'm pretty sure I've heard of this problem before from reading various posts on boards.
I will say the service adviser has been really great in keeping me updated frequently with this.

 

[mybluecorvette]

Sounds like the clutch is not properly disengaging


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[Steveinaz]

This shouldn't be that difficult because previous Corvettes have had manual transmissions and the functionality is basically the same. I agree with 'mybluecorvette' in that it sounds like the clutch isn't totally disengaging. You might consider calling around to other Chevrolet dealerships, if there are any others close, to determine if they have more experience with manual transmission Corvettes. Not knowing the entire situation, I would think they would be bending over backwards to find the problem and get it repaired. The factory might need to know the problem in case it affects other units. I hope they find it quickly and that it's something simple. I'd hate to see you go through some complicated situation with your new car.

 

[booie]

I dropped my C7 off at the service dept Monday morning so they could check something out. Shifting from 1st to 2nd is really stiff and crunchy (after 900 miles) and when the clutch is disengaged it makes a loud clank. I cannot even tell you when it happened, but I can say I noticed it when the radio was off and the windows were down. I did feel the crunchy shifting before that, though, and I thought it was something I was doing incorrectly or it was normal.
So it's been there at the dealership for a few days and they're stumped. They admit something is not right, but they can't diagnose the problem. Their first step is to compare it to another 7 speed C7...but there isn't one.
I have to wait until they get one in. Does this sound like a normal process, or should it not be so difficult to identify the problem? I understand it's "all-new" but I'm pretty sure I've heard of this problem before from reading various posts on boards.
I will say the service adviser has been really great in keeping me updated frequently with this.

Have you been driving mainly with or without the rev match on?

 

[JCobalt]

Thank you mybluecorvette and Steveinaz. I will call some other dealerships in the area. For 'booie', I mostly drive with rev match on.

 

[akpancake]

sounds like a broken pressure plate spring.

 

[JCobalt]

sounds like a broken pressure plate spring.

Thanks. Am I right to assume that this would cause the clutch to not fully disengage?

 

[akpancake]

that is correct, if the pressure plate has a broken spring the pressure plate is automatically warped, and cannot fully disengage. The diaphragm spring, when broken, can make a popping sound when the clutch is disengaged, or while engaging.
I certainly hope this is the case, because it is the simplest, and least worrisome to other 7speed owners.

 

[JCobalt]

that is correct, if the pressure plate has a broken spring the pressure plate is automatically warped, and cannot fully disengage. The diaphragm spring, when broken, can make a popping sound when the clutch is disengaged, or while engaging.
I certainly hope this is the case, because it is the simplest, and least worrisome to other 7speed owners.

Thanks very much! I hope so, too.

 

[Chip]

sounds like a broken pressure plate spring.

This is what it seemed like to me as well, but it well might be a defect in the pressure plate also.

 

[JCobalt]

This is what it seemed like to me as well, but it well might be a defect in the pressure plate also.

Chip, have you heard of this happening before in your research?

 

[Chip]

JC; I have not. There have been several other owners complaining of gear box noise, but not like what you describe. I will keep an eye open, but I hope you will find out sooner. Please keep us updated and good luck!

 

[JCobalt]

JC; I have not. There have been several other owners complaining of gear box noise, but not like what you describe. I will keep an eye open, but I hope you will find out sooner. Please keep us updated and good luck!

thanks Chip, will do

 

[JCobalt]

Update: I got the car back, but they changed their mind about something being wrong. They said there's nothing wrong with it, those clunky sounds are normal. So I suppose I should just enjoy this 70k clunker.
I'm not very happy with the way these issues are being handled. I'm going to try one more dealership before I sell it. It's just too embarrassing to drive anymore

 

[rdslon01]

Update: I got the car back, but they changed their mind about something being wrong. They said there's nothing wrong with it, those clunky sounds are normal. So I suppose I should just enjoy this 70k clunker.
I'm not very happy with the way these issues are being handled. I'm going to try one more dealership before I sell it. It's just too embarrassing to drive anymore

JCobalt, I am going to ask a really foolish question here, but I am trying to be helpful, so don't laugh at me too much. I have noticed that the base of the gas pedal in the C7 is really far forward from the firewall/floor. When I pushed the seat far enough back so my knee wouldn't hit the bottom of the dash (I have long legs), I was then so far away from the firewall/floor that I could not comfortably push the clutch pedal all the way to the floor unless I twisted my body slightly to the side (squirmed in the seat).

Here is my foolish question: are you sure you have been pushing the clutch pedal all the way down? It is not easy to get it to the floor, especially with the wheel well so close on the left side, too. At least, it was not easy for me.

By the way, I was told by many people that the clutch fully disengages several inches before you get to the floor, so full movement is not necessary, but maybe yours is adjusted differently.

I hope this might be of at least a little help to you.

 

[JCobalt]

That's actually a good question and I appreciate it. The answer is I do push it all the way. That was one of the first things I looked at before I took it in. It's much clunkier/louder when rev match is on, so it's possible I may have developed some bad habits in my laziness.
Things break/stuff happens and that's not what I'm upset about. I'm disappointed because this is the second C7 I've owned in which they refuse to acknowledge there are any issues. I love this car and I really don't want to sell it.

 

[rdslon01]

That's actually a good question and I appreciate it. The answer is I do push it all the way. That was one of the first things I looked at before I took it in. It's much clunkier/louder when rev match is on, so it's possible I may have developed some bad habits in my laziness.
Things break/stuff happens and that's not what I'm upset about. I'm disappointed because this is the second C7 I've owned in which they refuse to acknowledge there are any issues. I love this car and I really don't want to sell it.

This is the second C7 for you?! What happened to the first one?

I understand how frustrating it can be when someone (like employees in a service department, whose job it is to try to fix something) will not even acknowledge there is a problem. At first there is hope; then, not only is that hope momentarily taken away, but it is sometimes done with such finality that you get angry with everything even remotely related to the problem. The worst part is then if they try to somehow make it seem as if you are imagining something. How frustrating...

I hope you can find another dealership with employees willing to dig deeper to really determine what is going on. Also, if another dealership has more volume, maybe they have more experience with M7 transmissions in the C7.

 

[JCobalt]

Yep, the first one had so many issues I didn't post about them. The main problem was the automatic fuel management that constantly changed from v4 to v8, back and forth no matter what I was doing. It made a terrible scraping noise that was also embarrassing. That car was an automatic. When I first got the M7, I tried it out in Eco mode just to see if it had a similar problem, and it worked beautifully like it is supposed to. I've had other cars with AFM and I know it's not supposed to switch constantly and make scraping sounds that make my passengers ask "what the heck is that?"

Looking back, I should have made them fix it, but I was tired of taking in all the time.

 

[Chip]

JC; I am really sorry to hear this, it must be really frustrating.

 

[Mecholova]

JCob, I've been having issues with 1st & 2nd as well. Nothing horrific but it seems to clunk into gear a lot when releasing the clutch, especially in Sport mode. It's not sp prevalent in Tour or Eco. I thought I'd been away from manuals too long but it's almost as if you need to gun it in Sports to get it rolling without that clunk

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