Sadly, this is kinda what I suspect as well.
My "hope" was the fact that I had experienced ongoing power steering "leakage" problems sometime back and perhaps this had caused a bearing to begin going in the pump. BUT, it's holding fluid just fine now and the steering is quite responsive.
I'll hold off on expensive replacement options for a day or two just in case someone out there has had similar symptoms that were caused by something OTHER than the differential. If so, I'm all ears...
Thanks!
-Dan