TheKomoman

Took our '08 Z06 up to Mosport last weekend to watch the races and it has developed a noise in the driveline. The noise only is there under load so I would think it's either the trans or perhaps the torque tube. I don't hear it in 1-4 but with the engine sound in those gears it's hard to hear much of anything, when highway speed cruising in 5th or 6th with the windows up it's very obvious, somewhere between a buzz and a hum and the pitch does vary with speed. Took a quick video as in this case the recording is worth more than 1000 words I think. At the beginning of the video the noise is there, then when I lift it disappears, reappears when going back to the throttle, repeat.



Thoughts on the likely culprit? It's out of warranty so I'd like to have an idea of what I'm up against before I start spending money. Thanks.

sevinn

Sounds like what my 05 did before replacing wheel bearings. Does it get better or worse when you turn? I thought mine was driveline noise at first too because the noise was worse on throttle. Just an idea though it could be anything.

Good luck!

TheKomoman

Thanks. I haven't noticed it at lower speeds so I can't say I've noticed anything regarding turns, but again that could be because of increased engine noise under greater loads. I don't think it's wheel bearings because those are typically more howl than buzz like this, and the car only has 13,000 miles on it. But as you said could be anything...

The trans was rebuilt under warranty 2 years ago with every gear & counter-gear replaced except 4th. At the time I had full confidence in the tech who repaired it but recently my confidence has been shaken a great deal so I can't help but think transmission.

5knives

Sounds exactly like the problem a few of us are/were having. Some think it is the trans but most believe it's the rear diff.

http://forums.corvetteforum.com/c6-t...nsmission.html

http://forums.corvetteforum.com/c6-t...d-and-omg.html

TheKomoman

Fantastic, thanks so much! I couldn't come up with what seemed a logical search but that first thread you posted has any number of folks describing what sounds like EXACTLY the same issue. Did you ever find resolution to your issues?

5knives

I personally did not and have been dealing with it for a number of years now. Most members, including a few trans/driveline shops believe it is the rear diff. However, one member, ccmano I believe, replaced his rear diff and the noise was still present. He then wound up replacing his entire trans and the noise disappeared. So even with a qualified diagnosis he wound up spending money and not having the problem corrected right away.

My trans is stock but I have aftermarket 4.10s so in my case I would assume the aftermarket part is the issue (rear diff). However, in your case the trans is aftermarket/rebuilt so you'd think that would be the issue. We can't seem to get a definitive diagnosis. Damn frustrating if you ask me. My noise has not worsened in probably close to 3 years and there are no drivability issues so I'm not too concerned with it as of now. Ignorant maybe but they say ignorance is bliss.