I don't know what kind of oil is in it. I've had the truck for less than a month. Same about the shaft bearing. I just went out to the truck to snap a couple of pictures of the engine bay (I'm trying to figure out a missing hose situation) and for fun I started it up. It grinded just a little bit in first and reverse, and that's with having had the clutch in before the motor was started.

Currently I feel like I should find a used transmission/xfer case in good shape and swap it in along with a new clutch. The truck has 334K miles and maybe its time to replace the big parts.