Cherokee front differential locks

[94Cherokee]

My 94 Cherokee (full time 4WD) doesn't want to negotiate sharp turns in parking lots after an hour or so at highway speeds. Feels kind of like an old truck I had that someone installed "Lincoln Lockers" :lol: in- the front end kind of hops when turning. It turns fine most of the time.
Maybe I have the wrong diff fluid? This vehicle is fairly new to me, so I don't know the history.
Suggestions?

 

[Bounty__Hunter]

Is this a Grand Cherokee with no part-time option, or an XJ that you're running in full-time 4wd?

It's possible the viscous coupling in the transfer case isn't doing what it's supposed to after getting hot during highway travel.

 

[94Cherokee]

BH-
Grand Cherokee with no 2WD option. 5.2L.