I follow the procedure outlined in my owner's manual: back up & go forward 20 ft in 2H, shift transfer case into neutral, transmission into park, key to first position to unlock steering wheel.

Symptoms of the problem:
- When shifting from 2H to 4H, "Part Time" light on dash comes on, as it should. (This is a Select-Trac transfer case, so 4H is part-time, 4L is full-time)
- When shifting from 4H to Neutral, Part Time light STAYS on. I would expect it to go out.
- When I tow the Cherokee, the front differential gets REALLY hot, transfer case is also hot, though less so. This leads me to believe the front hubs are still in part-time 4WD instead of spinning free, even though the transfer case is in Neutral.

I've taken it to 2 mechanics who checked out the vacuum lines from the transfer case to the front axle, and they swear there are no leaks. I've put in a new vacuum switch on the transfer case, so that's not the problem. The second mechanic also looked at the solenoid and coupling/fork on the front axle, and couldn't see anything wrong with either. Everything should work as advertised, yet for some reason it doesn't.

2 things I've noticed that might be clues:
- While driving down the road normally (i.e. not towing it behind the RV), Cherokee will go into 4WD Part Time almost immediately when I shift to 4H. However, it takes a long time (sometime as much as a couple of city blocks) for it to come out of Part Time when I shift back to 2H. Mechanics tell me that there's one vacuum line that puts it into Part Time, and another vacuum line that takes it out again.
- The Blue vacuum line coming off of the transfer case is disconnected and plugged (up by the firewall). Nobody can tell me whether this is normal or not, but if they try to take the plugs out & connect the two ends of the Blue vacuum line, Cherokee will not come out of Part Time no matter what the transfer case is shifted to.

Everyone at Chrysler and at New Process Gear (the makers of the 231 J transfer case) tell me this Cherokee IS towable, and the front differential should not be getting hot like this. However, none of them can tell me what the problem is, much less fix it. They can't even tell me which of the 4 vacuum lines coming from the transfer case are for what, much less which one puts the front axle into 4WD and which takes it out of 4WD.

Having just spent almost $2000 on hitches, plugs & wiring, etc., I hate to think I'm going to need to trade this Cherokee in on a newer model just to get one that CAN be towed 4 down.

Having seen about a bazillion people towing Cherokees behind their RVs, I'm hoping one of you out there has experienced this problem and knows what it takes to fix it. I'm getting desperate!