limited slip?

Had my 99 cherokee rear end up on jack stands changing the diff. fluid. getting up from the floor onetime i made one of the tires spin. the jeep was in park and transfer case in 2hi. i could spin the tire around and around, the other tire spinning in the opposite direction. is this normal?:dunno:

Yup perfectly normal for an open differential.

having the diff cover off doesn't have anything to do with it though, right?

correct