Maybe it's a wheel bearing? I have an '06, and my front driver's side is bad, and needs to be replaced. I have two hub assemblies coming in tomorrow (going to replace both to be on the safe side). The things I heard were some crunching noises when pulling in and out of the driveway, and then some low moaning when turning the wheel, although that could be the ball joint in the LCA, which is also being replaced.
I didn't hear any squealing as you've described, however, now that I think back, I had the rear axle swapped out maybe not even a year after I had had the truck. I had heard this metal-like scraping noise coming from the back. The dealership said one of the rear bearings was bad, so they replaced the axle under warranty. I posted a thread here:
http://www.thenewx.org/forum/showthread.php?t=3118.
I hope this helps shed some light on the issue.