my 95 4wd 4.0L's rear end screams and whines when its on the road and accelorating it quiets down around 70 mph and when i let of the gas.... i've checked the fluid level and it seems fine. it says to use limited slip type fluid only but i have never seen the benifits of a limited slip off-road ( my rear right tire constantly digs unwanted holes while the left sits motionless) if anybody has any ideas it would be apreciated!