Metallic noise when in 3rd?
Thread Starter
Racer
Joined: May 2011
Posts: 306
Likes: 0
From: Orlando Florida
Metallic noise when in 3rd? Even when Clutch is engaged.
I'm hearing this noise, it's hard to explain, but a sort of metallic sound when I'm in 3rd. It's really odd because it's not always there (that's the reason why I haven't taken it in to Chevy yet). It also happens even if I have the clutch in (but it goes away the second I shift to neutral, and then comes back the second I move the shifter back to 3rd. It's just a steady noise that I can hear in the background (it's pretty loud though) along with the normal engine noise. It's a 2012 Grand Sport (6MT, obviously).
Does anyone have any ideas? I'm hoping the fact that it also happens when the clutch is in is a good clue on what it might be.
Does anyone have any ideas? I'm hoping the fact that it also happens when the clutch is in is a good clue on what it might be.
Last edited by flashburn; May 9, 2013 at 08:39 AM.
Melting Slicks
Joined: Dec 2006
Posts: 2,694
Likes: 106
Can you record it? Does it only happen with the car stationary? Can you hear it while moving? Sounds weird man. But is it really loud? These cars make a lot of noises when you're listening for them 
. But a loud one would mean something is wrong. Curious to hear it.
. But a loud one would mean something is wrong. Curious to hear it.
Thread Starter
Racer
Joined: May 2011
Posts: 306
Likes: 0
From: Orlando Florida
I need to check, but I don't believe it happens when stationary. It's loud, but not loud enough to record I don't think. It doesn't happen in any other gears, and the fact that it happens with the clutch in, makes it stand out as "odd".
Melting Slicks
Joined: Dec 2006
Posts: 2,694
Likes: 106
My approach is this: until you're absolutely sure you have a problem, meaning you can duplicate the issue at will, and you know it's not normal, I wouldn't bother wasting my time with a dealer.
My '12 GS finally has a nice engine (both LS1 and LS2 had piston-slap, and embarrassing valvetrain noise), but now the freaking tranny crunches on the 1-2 and sometimes 2-3 shifts when cold. It's perfect when hot. Since I found a way to get around that without having to skip 2nd altogether (not acceptable to me), I didn't bother to leave the car overnight so a dealer could confirm what I was telling them. I still have almost 2 years left on the bumper-to-bumper warranty, and almost 4 on the powertrain one, so I'm not worried at all. But yes, it sucks when the car doesn't funciton as it should at all times
. Oh well. But tranny work is a MAJOR job, so unless absolutely necessary, I don't want my car touched. In fact, if I had to do anything to the tranny, I'd probably just sell it. I can tolerate cosmetic stuff, but the reason I practically bought an old car is I didn't want any mechanical issues. After the 3rd time, I'm done with GM. But hope to keep this last GM car for a long time. It just needs to cooperate 
. Good luck man. And unless it gets worse, I wouldn't worry about it just yet. Enjoy it.
My '12 GS finally has a nice engine (both LS1 and LS2 had piston-slap, and embarrassing valvetrain noise), but now the freaking tranny crunches on the 1-2 and sometimes 2-3 shifts when cold. It's perfect when hot. Since I found a way to get around that without having to skip 2nd altogether (not acceptable to me), I didn't bother to leave the car overnight so a dealer could confirm what I was telling them. I still have almost 2 years left on the bumper-to-bumper warranty, and almost 4 on the powertrain one, so I'm not worried at all. But yes, it sucks when the car doesn't funciton as it should at all times
. Oh well. But tranny work is a MAJOR job, so unless absolutely necessary, I don't want my car touched. In fact, if I had to do anything to the tranny, I'd probably just sell it. I can tolerate cosmetic stuff, but the reason I practically bought an old car is I didn't want any mechanical issues. After the 3rd time, I'm done with GM. But hope to keep this last GM car for a long time. It just needs to cooperate . Good luck man. And unless it gets worse, I wouldn't worry about it just yet. Enjoy it.
Thread Starter
Racer
Joined: May 2011
Posts: 306
Likes: 0
From: Orlando Florida
Yeah, I've been hoping it would get worse, so that I could bring it in, but it's been doing this for the last 2-3 months, no better or worse.
Does the fact that the noise happens when the clutch is in mean anything? What exactly does the transmission do differently (something that is continuously moving?) when being in neutral vs in 3rd but with the clutch in?
Does the fact that the noise happens when the clutch is in mean anything? What exactly does the transmission do differently (something that is continuously moving?) when being in neutral vs in 3rd but with the clutch in?
SUBVETTE
Joined: Jul 2006
Posts: 3,841
Likes: 93
From: San Diego CA
Could be a noisy throw out bearing in the clutch assembly if you are hearing it every time the clutch pedal is pushed in. You would hear it anytime you push the pedal in regardless of the gear you are in.
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Thread Starter
Racer
Joined: May 2011
Posts: 306
Likes: 0
From: Orlando Florida
Nope, it happens either when the clutch is in or out, but it has to be in 3rd, and it the sound continues the whole time it's in third.
Melting Slicks
Joined: Dec 2006
Posts: 2,694
Likes: 106
That's very weird man. If it was the tranny shaft, it'd also happen in 4th, since it's shared. But I also have no explanation why the crunching when cold, when it's not the synchros. Unless it gets worse, just chalk it up to the nature of the beast. However, what I'd do is change the fluid to synthetic (I used Amsoil TorqueDrive, but you can use any synthetic fluid that is Dexron III compatible), and also adjust the shiftbox to make sure it's perfectly centered. In addition to that, I also relaxed the shifter detent with 1 washer, but that's not going to change anything in your case. Good luck.
Race Director
Joined: Mar 2010
Posts: 16,012
Likes: 828
flashburn,
I understand that you're waiting for this condition to worsen before visiting a dealership. Keep us in mind if you decide to go in; we're available to follow up and/or document any concerns you have.
Regards,
Sarah
Chevrolet Customer Care
I understand that you're waiting for this condition to worsen before visiting a dealership. Keep us in mind if you decide to go in; we're available to follow up and/or document any concerns you have.
Regards,
Sarah
Chevrolet Customer Care
Thread Starter
Racer
Joined: May 2011
Posts: 306
Likes: 0
From: Orlando Florida