updates??? :pca1:

Nothing yet. My next move is to remove the drive shaft and have it balanced. It was tough finding a place that does it. Just having trouble finding the time to get it done.
I'm moving next week and once I have my heated garage, I'll be climbing under and taking a look.

very possible a weight fell off, with everything you've done that should be the next step.

:pca1:

An out of time driveshaft can only happen to a two (or more) peice drive shaft. The u-joints have to be in the same position from front to back, in other words the caps have to be horizontal and vertical from front to back. If they do not line up there is prob 90 percent chance you will get a vibration. Ive seen drive shaft shops send reman shafts back to customers out of line, think they are creating fun by doing that I guess.

Is that a long bed 2-piece rear shaft or a short bed 1-piece prop shaft?

I havent worked on too many (or any that I can think of) newer shortbeds that have a 2 peice driveshaft. Usually they have a slip on the back of the transmission or transfer case. Now older trucks that have the driveshaft yoke that bolts to the transfer case output shaft will have a slip joint inline and it will be a 2 peice shaft. Not sure what years and models the 1 or 2 peice shafts are in. Look for a rubber seal or a boot on the shaft. If its there its a 2 peice.

Where does it say it's a short bed?

Is that a long bed 2-piece rear shaft or a short bed 1-piece prop shaft?

Didnt you just ask that? Was responding to your post #25

have the flywheel checked , a common vib. problem w those trucks....

So, to the OP: What is it - Long Bed or Short Bed?