from own experience aand what I read in this valuable forum, is the front differential (the bearings are worn) and that cause the noise. Why? the differential lost oil somehow.
You have to
1 chenge the bearings inside the differential
2 get a new differential (if can be sold separated from the transmission), or
3 get a new transmission,
good luck, and since I have the same problem please share your info if you know about a place to get either the differential or the tranmission
thanks