I have the 8.8 3.73 Limited slip rear end, It makes a chirping noise and I was told it was the clutches? Can someone explain this stuff to me? I dont get anything about Limited Slip or How I fix that stuff... 
Thanks Ryan!!

Thanks Ryan!!

Is it pricey?
I agree with Sasquatch. It's about 12 bucks for a 4 oz. bottle (all you need) at the Ford dealer here.
EDIT: Wow, it's much cheaper through Summit. How close are you to Summit Ryan?
http://www.summitracing.com/parts/FMS-M-19546-A1