242 Tcase, no 4 high

1998 XJ bone stock, 2wd works fine, 4 low works fine, but no 4 high, just the rear tires spin, dosnt matter wether its in 4wd part time or full time, 4 high just dont work, anyone had this problem or got thoughts or sugestions?

neither part or full time work? How did you check it?

part time and full time do not work, had a friend check and see if the frt tires were turnin, this was out wheelin and they wernt, had it happen a few other times to but 4 lo works fine