First, find the make and model of the transfer case.
THEN you can research that particular case for towability.
Yes, there is a modification for certain transfer cases that welds splash vanes to one of the sliders in the case. I don't remember which case that is for, though.
Yes, WARN used to make a full-floating axle kit for certain Jeep rear axles (IIRC, the AMC 20 axle). I installed one on a Tuxedo Park CJ many years ago. It was a great kit. With WARN hubs on all four wheels, towing was a snap! I have heard that the kit is no longer available due to lack of interest.
Most assuredly you should get the Owners Manual, whether you find one on eBay or download one.
I dug around my bookcase and found my 1977 CJ5/CJ7/Cherokee/Wagoneer/Truck Owners Manual. Here is what it says:
Automatic transmission WITHOUT Quadra-Trac Low Range Reduction Unit:
Ignition OFF, not locked.
Disconnect front and rear propeller shafts at the axles and secure the shafts to the underside of the vehicle or remove them completely.
Automatic Transmission WITH Quadra-Trac Low Range Reduction Unit:
Ignition OFF, not locked.
Automatic transmission in PARK
Low Range Reduction Unit in NEUTRAL
CAUTION: If the emergency Drive Control knob (in the vehicle glove box) was in the Emergency Drive position when the engine was hut down, restart the engine and turn the knob to the NORMAL position.
NEVER TOW WITH THE CONTROL KNOB IN THE EMERGENCY DRIVE POSITION OR THE LOW RANGE REDUCTION UNIT IN LOW RANGE!
Here are the instructions for manual transmission units:
Ignition key OFF, not locked.
Shift transmission and transfer case to NEUTRAL position.
Turn selective drive hubs (if equipped) to LOCK position.
The above is from page 70 of the manual.
CM1, USN (RET)
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