I seen and read issues others have had with front ends but mine is a little different. I have an 04 Rubicon. 3" body lift that is all. When I drive it at a slow speed it hears and feels like I am driving a tracked vehicle. I jacked up the front and can hear/feel the noise when spinning the front tires. The axle ujoints are ok. I kind of thought the wheel bearing but I took them out and they spin smoothly by hand. If I turn the axle shaft with no wheel bearing I can still feel the and hear the noise but not a prevalent when I drive it. I took the diff cover off and there was nothing unusual there. I also removed the front drive shaft and drove it to see but the noise is still there. I noticed if I'm driving it and give it gas the noise will change. at highway speeds is seems to turn into a vibration.
I was thinking the Pinion bearing, but not entirely sure on that. I bought the kit from G2 for the diff overhaul that was done about a little over a year ago. so I would be a little surprised if it was the pinion bearing.
Please help hunting season just started and I need my Jeep to take me to the cabin so I can hunt.