Strake

Just saw Bruce's reply...... I like the idea of as many of us as possible sending GM Exec office with an email. If you want to send me a PM with her email address and name, I too will be happy to send her an email.... WITH my video clip.

I'm with you Bruce...... WHY won't GM Engineering take a known WARBLE noise car and determine the root cause, and come up with a fix for it, then do a TSB ???

Highplains

Yes. The URL provided a link to the YouTube video

Highplains

The address of the GM CEO is mary.barra@gm.com Maybe we can ring some bells if more than one sends mail. Like I said, you won't be hearing from her but some sort of assistant. You'll see a call from an 866-790-****. She'll ask a bunch of questions about what's going on. She then will be calling your service manager. My guess is this CEO gets a ****load of emails like this every day and these assistants are there to smooth things over. I hope this is more than just a pacifying process.

Highplains

You mentioned in a recent post that GM wants to change out your diff. You may be aware of this but I just ran across a post on the Stingray Corvette forum from a JBC9845 who appears to have the warble noise. GM changed out the trans, diff and axles and it apparently worked at first but then came back. You may want to point this out to your dealer or engineer. Makes me wonder about the engine lugging and wearing on the diff. He may have had to wait a few miles before it wore things again in the new diff and the noise starting again. That would speak to the shift points in the trans being at too low an RPM. I have a private message in to this guy. Hopefully, I'll hear from him.

bjones7131

I just sent GM CEO and email outlining my/our problem with the strake video asking for GM eng. to get a demon test stingray with the issue and do a root cause and find the problem and then generate a TSB. My dealer called today indicating the new rearend was in and to call and make an appt. I told the CEO or whomever reads the email I wasn't taking my car in until I heard form someone in her org. I hope we will get to the bottom of this. Trading for a mustang sounds better and better, LOL

Strake

I just added a response on the other forum, same thread you referenced this evening. I added my YouTube video clip to that thread.

I also added a comment on my YouTube video page:


Directing my comment to GM Engineering, hoping that they are watching it. I also referenced BOTH THREADS on BOTH Forums covering the same topic. Hopefully, GM Exec's and their Engineering counterparts will see the common thread ( pun intended).

Richard

bjones7131

I just updated the FB group and indicated I sent the CEO an email to the address posted by Highplains and one of the FB guys said that wasn't the CEO's real email and it was monitored by customer support so who knows. He said he was a top chevy seller in the country and he had her real email. Whomever is monitoring the email I just hope we get results. Later guys
Bruce

Highplains

Shoulda known. Another cog in the big machine.

Highplains

I just received this email from a man I communicated with about the warble noise:



"Yes, I had this problem and it was pretty severe with less than 6000 miles on the car. I could reproduce it at will both in town and on on the highway. The rear end, trans, diff and axels were changed out. The noise in now much, much less but its still there. I only hear it sometimes at highway speeds.


I've told the dealer that its not the rear end the problem, in my opinion is with the capless fuel filler tube, Everytime i hear the noise it is right behind me on the left side of the car right at the hight of the filler tube. When they replaced the rear end they must have moved the tube ot tightend it down or something.


If you have the oportunity stick a gas funnel tube into the gas filler tube, drive it around and see if you still get the noise"

bbcb

if are correct ..GM should send you a check .... and at the same time fire a few engineers ....

Highplains

Hell. I'd just settle for some engineers that would just own-up to the problem and tell me they'll help the dealership fix it if indeed it's a situation worth tearing-up the car.

bjones7131

I am sorry but i find it hard to believe it is the fuel fill tube. I think we A8 and non z06 are the ones with the problem, and i assume all c7 corvette fuel fill tubes are the same so this alone tells me it is not the culprit.

Strake

I'm still in the camp of a harmonic resonance issue, and to me the Torque Tube somehow makes the most sense to me.

Highplains

What do you think produces the resonance? That's the part that bothers me.

Strake

Wish I knew, LOL If I did, this would have been resolved for all of us by now.

I'm thinking something out of balance, at a given rpm range ( 1300 - 1600) in a spinning environment could cause a sound resonance. With the fact that it's tied to RPM, and not speed, or gear, I keep thinking something to do with the Torque Tube...... but I'm not that clear on how it all works together from the engine through the tube, to the transmission, differential, axles, and wheels/tires ....... as this isn't your typical rear wheel drive set up

If someone can spell it out front (engine) to back of how each of the major components line up, and their primary function, that would be very helpful...... or easier yet, if anyone has a diagram of it that might help to understand.

thanks,

Highplains

To My Brothers Of The Warble:

(I couldn't resist that.) It appears that the squeaky wheels may be getting greased. I received a call this AM from an engineer for GM in Corvette Quality Control. He was very interested in my email to GM as well as the video that was posted (By Rich?). In fact, he said that he wants to round-up a team of fellow engineers, come out to Kansas and take a look at my car. He described bringing instruments with him to help determine the location of the noise. He's thinking about the "H" pipe in the exhaust-something they have already been looking at and also wanted to know if I'd ever had the diff changed out. In any case, all of this may happen as soon as next week. He had already called my service manager who told me that it has been his experience that when one of these teams comes out, they are there to do the whole enchilada i.e. diagnosing and fixing the problem on the spot

So Bruce Jones, tell your dealer to hold on to that diff. And to Rich (I'm not sure I've got the right person) the video really helped. Since the GM folks have responded in a meaningful way, I have decided to be the test mule for this mess if it comes to that. Hopefully, it is a poorly designed exhaust and not the diff. If it is the exhaust and they can assure me that the noise does no harm, I'm thinking of just leaving it that way to minimize tearing into the car. But whatever the case, I'm going to let them go ahead with the inspection. This guy seemed very enthused and up for this. My service manager says that he's seen these guys fly in, bring their instruments with them and first-day air in any parts they need and fix it on the spot. Should be quite the sight.

So what do you folks think? Needless to say, I will keep you informed. The engineer is supposed to call me back this PM.

Strake

Highplains,

Encouraging news that at least you are getting some Engineering support to address the issue.

Glad to hear the Video clip I made helped them to hear what's up.

I'm going to send you a PM with my contact info, just in case those folks want a list of who's also involved with this. EDIT: PM SENT to you and Bruce Jones.

Keep us posted

Richard

bbcb

suggest just giving you another car ...tell them to take that car and noise back to the plant ...for good ...where it belongs

bjones7131

Arctic C7 from GA hendricks dealership just posted a few days ago about them changing out his exhaust twice and then finally narrowed it down to the X pipe but it was a different noise so I would be shocked if that is the problem but who knows but his case proves it isn't our problem in my opinion although I didn't hear his but he stated in his post that is noise was different. He also stated his noise would go away when the afm valves and baffles were un-powered via removing the fuses that control them. I did this and nothing, my noise was still there. On the other hand if it is the problem I would let them change it out and be rid of the noise as long as they don't screw something else up in the change out like my rear bumper. Exhasut change out is not that radical so that is the reason I opted for that on my car. I believe I remember U saying they had a demonstrator vette at your dealership that had the same issue, why not let them have a crack at that one instead of your car if that is an option. I just got the same call from my service manager with the same info about GM coming down from Detroit with eqp. and want my car for some time to figure out the problem. They want to do this before the rear end change out. They said I coudn't interact with them at all and had to go through my service manager,(my reputation preceeds me, LOL). They will provide me a loaner and I was adimate about not crewing up anything on my car. My dearer said he had never had this level of support in his time at the dealership. I firmly believe the emails we sent got the attention we have been asking for and the video/audio was a big plus. He is going to call me back in the PM after he talks back to the Eng. folks and works out the details. He just wanted to make sure i could bring the car in. Thanks to all who have helped push the rope and herd the cats.

Vettetrax

I have a 16 with 2700 miles, NPP, LBR, NAV. I have the same issue when, ever so slightly accelerating. If let off or push it into V8 no noise at all. Had it to the dealer twice and they said the axle lugs needed to be torqued. Was OK for a while but now it's come back occasionally and seems louder. They had it for a week the last time so I'm going to wait to see if it gets any worse or even louder.