It is my fear and sudden dread that it's time to replace the diff...
Thought I bounce this for mental health reasons here...

All of a sudden my '93 245 auto with a 3.73 diff started plaguing me with increased vibration and bass type noise coming from the rear.

A bit of history: I repacked the rear bearings 2 years ago and replaced diff fluid. Everything was fine since then. Curious though that then I felt that the half-shafts never turned smooth. Think that's normal???

Fast forward to now: Lifted the rear off the ground and checked out that it does not matter which wheel is spinning. Noise and vibration is more pronounced and gets loudest 20-40 mph. I have yet to pull the wheel and brake hardware off. Took a look at the diff fluid and no sign of metal, but did not take off the diff cover.

Basically sounds like I am driving on grooved side pavement from start and then have a helicopter flying right over me wherever I go faster with increased noise and more frequent vibration.

I looked at axle and the U-joints seem ok. there is a bit of play at the
support bearing.

Bearing or diff or perhaps axle?

Anyone want to help with diagnosis near Willimantic, CT?