Random vibrations at different speeds and torque.
No squeaks or squeals heard.
Recently replaced harmonic balancer/pulley, 1pc/welded together. Now a few weeks later feeling vibes in the rear 247,000 miles, 5.9 and runs like a champ after many new parts from lack of maintenance! 200$ disposable. Any thoughts or opinions appreciated.

 

How old are the U-joints? Last time fluid in the rear diff was checked/changed?

 

just recently bought it as a 200$ disposable and unsure.
Pumpkin is full and appears clean

 

Yeah, have a look at the rear joints, and driveshaft in general. Probably wouldn't hurt to check the lugnuts as well.