You have to turn the yoke and chock one wheel to tell you wheter or not it has a no-spin(detroit) locker. The locker will engage and you will not be able to turn the yoke. If you just spin a tire, you might hear clicking sounds. With a limited slip, both wheels will turn one way if you spin one, but a locker can disengage and act like an open diff. FYI, the Eaton H052/072 rear ends did not have POSI, limited slip, gov lock, trac lock, power lock, or anything else other than a no-spin. A locker is still available new via a corp 14B and its shafts
Does the carrier have the pinoin pre load bolt, and how bad is the backlash (measured in thousanths of an inch.(how far the pinion will move before the teeth engage the ring gear)