I believe it has something to do with the oiling.

I KNOW that the towing manuals said not to tow with one diff contained and the other moving.

 

While some splash lubrication takes place the transfer cases do have a small oil pump driven by the rear output shaft, so if the rear driveshaft is spinning, the pump is pumping oil, but maybe it is better to think of it as simply distributing oil to areas that do not get oiled well by splash. The pump does NOT make much pressure or provide oil to all points, just some modest flow to areas that need it most.

Now, the Neutral position disengages the transfer case input from the transmission and while it theoretically disengages the front driveshaft and rear driveshafts there is still considerable drag between the 2 since the primary chain is still spinning both shaft gears. For short tows of a just a few miles you can get away with it but travelling hundreds of miles, especially at highway speeds can damage the front output shaft since the rear driveshaft is turning the primary chain and that gear is spinning on the front shaft with little or no lubrication. If you examine a blow-apart of the transfer case, or better yet, as I recently had to do, rebuild your transfer case, you can see the problem.

 

^^^ Excellent answer right here ^^^

 

Where can I find a tow bar for my 1992 XJ? Would be great to bring it behind the RV! Any old universal one??

My 92 has the 242 TC.. So TC in neutral and in PARK when flat towing..?

 

yeah, pretty much any tow bar. but it has to be set up so the angle isn't too steep. should be as level as it can be. also, proper attachment points and tow light harness has to be used.

and yes. TC in neutral and transmission in PARK every time you flat tow.
you will need the key in the on position, obviously to get the trans in neutral to be able to shift the TC into neutral, then shift trans back into park and leave the key unlocked in the far back position as so no lights are left on in the dash. that's the actual proper way, but many will say to lock the steering, i've done it both ways, but i too am a certified wreckmaster tow operator, and this is one area we covered.

 

I put atf in mine.

 

Pull the rear DS and strap it up...........jeeesh.........


Takes 10 minutes.


Be done with it.

 

Correct. ATF is what should be in there.

 

I'm finding tow bar setups from $100 that mount to the bumper to $1000 rigs that have a "plate" that bolts under the bumper.

I imagine that I can get the bumper mount one and weld up some beefier mounts.