Sounds like transmission to me. I would check to see if the transfer case is stuck in between setting first and check your transmission linkage too. I have experience with the same issue, if there is no engagement and it is going into gear it sounds like the clutches in the transmission are burnt up.
1983 Jeep Wagoneer-322,000 miles.
1972 Jeep Wagoneer-360-auto-sold
1988 Jeep Grand Wagoneer-One owner-64,000 original miles-Sold unfortunately
1968 Jeep Gladiator, full Resto in progress
1963 two door ifs one owner Wagoneer