You sure it's the differential? I had a front wheel bearing / hub go on my Titan about 4 or 5 yrs ago. Made alot of noise. Like a grinding noise. The other one had a little play in it last year. Had it replaced. But that one wasn't making any noise at the time. My front hubs didn't last very long.
I'm not sure I just installed a 6in lift this weekend and had the front end out I free spun the axles didn't hear any noise but the driver side axle does have more play than the passenger.thebearing I spun them and they was smooth but there was just a hint of noise from both of them no play tho. I don't hear any noise when I'm driving and turn the wheel side to side so kinda stumped