a week ago I noticed an intermittent clicking noise while I accelerated. I didn't notice any change while turning, but it was definitely only happened while accelerating. It also clicked in tune with the tires, I'm guessing one click per rotation. I planned on finding and fixing the issue shortly, but since it was only present every so often I put it off. Then the other day I was changing lanes on the highway when I heard a loud pop, clunk, and then grinding coming from the front end. Naturally I threw it in neutral and stopped in the shoulder. Roadside testing concluded that it grinds going forward, though not terribly noticeable until about fifteen mph, and it locks up in reverse. Towed it home (covered under insurance ) and garage testing has concluded that cailpers, wheel bearings, and u joints are okay. With both front wheels raised I can spin each one forward independently, but if I try to spin it backwards it'll catch the other wheel and both will spin in reverse. While spinning the front drivers wheel forward I can feel the grinding in the differential housing and the shock. I'm really hoping it's not the differential, as I don't particularly feel like learning about diffs just yet. But I've also been having issues shifting through 4x4, particularly shifting into anything past neutral (full time hi and lo) and getting it to actually go back into 2wd (lever shifts fine but it doesn't disengage front power until a short distance on dry pavement.) So I'm wondering if I might be having issues in my transfer case that have caused all my issues, or if I have issues in my transfer case as well as probably my diff. Any insight? I need a fresh mind or two to look at my situation.

 

Take the differential cover off and have a look.