Vibration?

I'm getting a pretty bad vibration when allowing the truck to coast down below say 20mph, or if I'm riding in a parking lot in 1st or 2nd gear. It doesn't matter if the truck is in gear or not, so I figure it's either the bearing below the cab of the truck around the drive shat...2 piece shaft...that's going bad, or some kind of bearing in the rearend. Any ideas?

yep... carrier bearing is the word your looking for.. and yes they go bad if you have a poor pinion angle.. and will cause vibrations at various speeds

Could be a carrier bearing, could also be U joints or a bad tire, or possibly rear end problems....best to pop underneath and take a good look at everything.

Carrier bearing is the one on the driveshaft correct? I guess my pinon may be bad, lowered with 3" straight blocks and monoleafed :O