99 Durango Rear

Got some noise coming from the woman's Durango rear. It kinda sounds like a rubbing or low growl. It only happens at slow speeds and if I apply the brakes it goes away. I was thinking a spring or something broke and a shoe was dragging.....well i pulled the drums and everything looks fine. It does have a LS rear and I am wondering it it is the clutch plates chattering in there......I added 1 bottle of the MP lube last summer when I changed the gear oil maybe I need another bottle? Any ideas?