1995 4.0l 4x4 5 speed manual Foed tow package 190k
I am 1,200 miles from home. Drove here towing a 1200 lb gross tailer and the truck started to make a matalic whirring sound like a bad bearing. At first just in OD then 3rd now a little in every gear. Shifts OK, a little stiff but it has always been that way. Gets louder as it gets warmed up. I seem to have read somewhere that there is a bearing that commonly goes bad. I need to get back home towing the same trailer and my route is from So CA to the far end of Oregon with 3 sets of good hills to climb. Is failure imminent? I need to get back home before I can swap the trans for a rebuilt one if that is needed.

I am going to change out the trans fluid and transfer case since I will be there anyway. Is there anything short of replacing the trans to help?

TIA