Re: diff noise
Welcome to the garage.
It can be something easy as a low fluid level, to something more serious as worn bearing(s) or pinion/ring gear. I would start with changing the fluid and as you will be in there, check the fluid for metal glinsters (best seen in shadow place with a strong flashlight on the fluid). Also check the ring and pinion for abnormal wear signs.
JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
Monroe Reflex shocks /
Pirelli Scorpion ATR 245/65/17/
Transgo reprogramming shiftkit.