truck cab vibrations

He may have seen worse. Here's the deal though, it's only going to get worse as its beating around. Go to YouTube and search for otrperformance. They have a bid of a blue Volvo doing a burn out. They show it in slow motion and you can see driveshaft and what it has to endure

 

I'm sure that's it. They only have one

 

They are referred to as "maintenance free". Just a way of saying "use it till it wears out then buy a new one"

 

I have the slightest vibration only during a hill climb with a load. The carrier bearing felt tight but, I dropped it and spun the bearing around the drive shaft, it spun freely but, sounded dry. I ordered a new Spicer unit and nut, will let you know if it helps.

How are your driveline angles?