You pull the transfer case shifter from 2wd to 4wd.
Any Jeep with a NEUTRAL position on the Transfer Case shifter. There a numerous Jeep owner/user Forum, all you have to do is search.
Remove the access plate on the floor to expose the trans. disconnect the transfer case shifter as 2 of it's bolts are shared with the shifter on the trans. The bracket is held on to the 2 left hand shifter bolts and will have nuts on the top to remove, it is not possible to just move it out of the way without removing the other 2 bracket bolts further down on the trans. Then remove the 4 retaining bolts on the top of the shifter and pull it out.
4 bolts, 2 up top where the regular shifter mounts, one on the side of the trans, and one more facing backwards, all on the bracket.
If it has a 2wd selection on the transfer case shifter, then yes. If it only has 4 hi and 4 lo, then no.
remove access plate on floor around shifter, 4 bolts hold the shifter onto the trans.
under the jeep your transfer case remove the bolt with an Allen hole in it with and Allen socket. the fluid should run out of the hole. if you remove the bottom bolt you will drain your transfer case. if you remove the top bolt then you will be able to check it and will not have to refil it.
On those you remove the top plug on the transfer case and pump fluid in until it runs out, it should be even with the bottom of the opening.
first most obvious, make sure the transfer case is not in neutral. If the shifter is stuck in one position you can access the floor panel over the shifter, then remove the shifter, sometimes when worn or loose they can become stuck and you can fix it by lifting the shifter out of the trans. Lastly, and you would probably already suspect this, the clutch is gone, but you would have had a lot of issues and slippage leading up to a complete failure.
Either the output seal on the trans or the input seal on the transfer case has failed. You will need to remove the transfer case to change both seals.
NP243
It is on the center of the rear of the transfer case.