I have a 2007 v8 2wd and there's a loud hum coming from my truck that at anything over 20 mph, sounds like just too much road noise for the speed I'm driving. I do have BFG AT tires, but this sounds like knobby mud terrains that have worn unevenly. It's way too loud. At lower speeds - 10-12mph - it's a pulsating sound and it happens while turning any direction and even in reverse. It gets quicker and quicker as the speed increases and turns into a constant hum around 20mph.

It sounds a lot like when my front bearings were shot, but I've lifted and spun all 4 tires, and it's not that. I'm thinking driveshaft. To remove, test and potentially replace, does anyone know if the 2wd is as simple as removing the 4 bolts at the rear differential and sliding it out? I've seen videos that all say mark the position so it can be reinstalled in the same way. But if I need to replace the whole thing, do I need to worry about installing it in the correct orientation?