I tightened the pinion nut "real tight" holding back with a large pipe wrench on the flange and torqueing the nut with a large socket wrench. The book calls for 160 foot pounds. I probably got close to that with a 2' breaker bar. The pinion bearings are perfectly smooth and run free.
As...
This is a new thread that follows up on the first.
https://forum.ih8mud.com/threads/rear-diff-1970-noisy-question.1335018/#post-15411372
I took the cover off the reaf diff on my 1970.
Briefly I had a vibration at highway speed in the diff. Tightening the castle nut on the flange "fixed" that...