I too experienced the rattly loose steering shaft. Truck developed the drive line clunk at 5000 miles. Repeat fixes helped but not solved the problem. Lately the drive axle had to be replaced. This breakdown occured while towing my boat. The Tow Mode switch also died on its own. All work was covered by warranty. I'm scared what will happen after the warranty expires with 5000 miles left to go. To that end, I'm trading it in for a new 2007 Tundra. First new vehicle bought, last Chevy I will buy.
I loved the interior spacing and comforts. Will miss it when compared to the plasticky Tundra.
Please build Chevy's more reliably or extend the bumper to bumper warranty to 5 year 60K miles.