OK guys. When backing up in first gear I am getting a creaking noise oscillating with rpm and tire speed. I thought it was my e-brake, brake pads, etc. but after tearing everything down and finding nothing I still have the noise. I don't think its a bearing.

It seems to be coming from under the middle of the truck but is really hard to tell. I was sure it was the drivers rear disk caliper but now am thinking u-joint.

Thoughts? Thanks, Kurt

 

If yours has the drive shaft carrier bearing that might be it.
Have you serviced the rear and forgot to put in the friction modifier?

 

inspect the U-joints if you see rust colored dust near the joints they are done like dinner, you might not find them loose (as the needles pile up, tightening the joint) but if you remove the drv shaft and rotate the u-joint thru its range of motion I promise if a joint is bad you will find it by this method, rarely is it the joint closest to the transfercase, almost always its the one closest to the rear diff that goes first (it recieves the most articulation)

 

Thanks guys. Nickg, you are the winner! That is exactly what I found on disassembly. Thanks!

Kurt