Well, here I am still jackin around with this issue. The rear has been rebuilt once, still making the whine. It's been back to the dealer several times. The fact is, when they rebuilt it, they didn't do it correctly. They even asked me to bring it back after the ring & pinion install, because they didn't have a tool needed to "adjust" it. My guess is they didn't have the lash set correctly. So, now I wait for them to "bench build" a complete new rear. When they get it done, I'll bring the truck back to they can replace the entire rear, housing and all.
Chrysler corporate is involved, but seems they either can't or aren't doing much.
Pretty sad treatment for a life long Mopar owner.