I took the truck to Moran Chevrolet in Clinton Township, Michigan. They wrote up the service order and got me set up in a rental car (that I had already put all my stuff in). Just as I was about to pull away, the Service Manager came out and wanted to go for a ride with me in my truck to see if he could hear the noise. During the trip, the noise was not as noticeable. However, when he did hear the noise, he said, "oh that's normal, they all do that. It's just the axel moving and hitting on the retaining pin." Now I've owned 4 Full Size Chevy trucks in the last 10 years, and I've never heard that noise before. Also, he told me that they were not going to do anything about it, because, "GM won't pay us for the rental car if we don't fix anything". That's a bunch of BS! I brought my under warranty truck to the dealer for a genuine problem, and I was told it was "NORMAL". I am sorry, but when there are service bulletins that cover that exact noise (TSB 03-03-09-002E), I am not a happy camper.