an additional piece of advice
I agree and aclknowledge that Wreckerman is absolutely correct. I would add this advice also:
Do not engage your front end when you have unbalanced rotation of your wheels. I am saying that if you are spinning your rears. STOP!!!!! Engage the front end. Then proceed. If you drop that front end in with the driveline under motion, I am afraid to think of how many little bits and pieces you can turn some of the gears into.
If you are under "normal" motion, i.e. not spinning; You can engage your front end, but because it is air, you have no way of judging whether it is engaging nicely or not. I generally know I will need the front end engaged before I get into trouble and try to always shift while stationary.
The deuce is very different than a typical older 4x4 with a one or two lever transfer case. The air shift is pretty forceful. You have not a clue as to how easily the gears are engaging; or are NOT ENGAGING for some reason.
The new 4x4s or "all wheel drives" (AWD) have synchromesh and all sorts of wonderfully expensive parts to allow you to engage your 4x4 at speed.
Since I have to fix my own vehicles, I like the dinosaur technology of the vehicles I have.
Just my two cents, and if I am mistaken on some point,
I am never offended by someone bringing it to my attention!
Knowledge is power!
RL