took the truck to the shop here in spokane, was advised that the noise I am hearing is coming from the rear axle...we lifted the truck in the back and placed jack stands on the axle and started the truck, put into drive and listened. The noise is more predominant from the left rear...inside the axle.
called my dad and he said its possible its the carrier bearing or its inside, axle bearing or weights and or a nylon bushing has broke? the tech guy used a stethoscope to listen to the axle, its on the left side inside...they dont have the tools to fix it...is this VERY serious and is it going to cost me an arm and a leg to fix, can I fix it myself?

 

I would say the bearings are bad in the rearend, I would not run it anymore because if the bearings detonate inside the housing, you lookin at alot of money for the repair