This noise is driving me crazy!!!

[solarflare]

I've had my 07 H2 for a while now, and was driving a 2010 Rubicon for a few years. Finally got sick of not having much room in my Rubicon, and decided to purchase a 2009 H3 Championship Edition. Love the truck, but it's had a strange noise that I can't diagnose, nor can the dealer. It's driving me crazy. Here's the info:

2009 CE with 5.3L engine
24,000 miles
underside is clean, no rust.

1) This noise is loud. On a scale of 1 being you have to listen to hear it, and 10 being it sounds like a hammer hitting your door panel, it's a 12!
2) It only happens when taking a corner, mostly to the left. It will also happen if you turn right, but not as frequent. It's kinda like you hear the noise when you turn left, and then if you turn right you will hear it again, and then another left turn it will do it again. It's a back and forth issue. You can feel it in the floorboard as well.
3) The strange thing is it will completely disappear if you drive in the rain. It will stay completely gone for a few days, after a rainy day, until whatever got wet drys out. As long as it's raining it's a perfect truck! There is no noise, and you can't feel it in the floorboard.
4) It is coming from the right rear passenger's side. I had someone hang onto the outside of the truck as I made a slow turn...and they located the noise in that area. Just can't pinpoint it.
5) The sound is a metallic sound, like metal to metal, and sounds like a person is hitting your rig with a hammer.

I have gone over this 3 about 10 times. Everything looks good. Checked the body mounts. Checked every bolt under there to make sure it is tight. Put new shocks in. There is no visible evidence or wear showing.
Brought it to the dealer...they hear it, but can't figure it out either. They said to just drive it. I don't want to keep driving it, if it is something that is dangerous.
Does anyone have any ideas what this may be? Anyone experience symptoms similar to this? If so, what fixed it???