I understand, I suffer the same affliction, it started with the front end (king pins,brakes, engine rebuild, tranny rebuild) slowly working my way aft.
I worked as a diesel mechanic for years so I've seen some wierd things go on with machinery. Another check is to try and move the output shaft back and forth, to see if you get some obvious play, if the aft bearing is coming apart you may feel it.
Hopefully its one of those cases where the previous doctor left a sponge or something in the patient. Good luck with Juanita.
