Here is a message I just sent back to the GM person on these threads. I think we really need to start hammering GM and not just the threads to get a resolution. I have had my rear diff replaced, sound came back. Replaced fluid started making the noise pulling out of the lot and still doing it after a few weeks of driving.
http://www.camaro6.com/forums/member.php?u=29125
My dealership has told me they have called in and that GM told them this is normal and that they are not to do any further repairs on my Vehichle for this issue. This is completely BS and I am not happy, actually worried is a better description. Since you are obviously on this Camaro6 forum you can see that there are a ton of people who are also having this issue with no resolve. Add me to the list of very unhappy, concerned owners. I would like resolution just as everyone else. At least assurances that GM recognizes the issue and is working on a resolution.