Getting rumble sounds from the rear of my Previa. Replaced the outer wheel bearings... but unfortunetly rumble is still there. Thinking it's the differential now. Van has 198000 miles on it. Apparently this differential is unique to the Previa and I can't find any US suppliers of after market replacement rings, pinions, bearings etc... any help is appreciated.

You can get a differential from a toyota 4 x 4. get one from the front end they have little wear on them. I did this when my seal blew out. Any shop that builds rear ends would know what interchanges. or ask a junkyard. Cost should be about $350 for who 3rd member or $350 to have a shop replace all bearings with labor. You take 3rd member out.