My wife has one I can't get her to give up. We have towed a lot of stuff with it and no issues. It has the 4.0 engine in it. Pulling a load I would kick out the overdrive up hills. Only thing I do is set the drive band a little tighter than spec when servicing the transmission and when we first bought it I turned up the valve body pressure over the stock setting. This tranny is just a glorified mopar 904.
The transfer case has a viscious coupling in it. If you are not in 4x4 and notice it jumping while turning on pavement, or even a slight tug like it is in 4wd when turning and not in 4wd, the transfer case fluid is dirty and is making the viscious hang up. When I worked on Jeeps back when these were new, they recommended quadratrac fluid in the transfer case. I cured many of these units from the viscous from hanging up by changing the fluid, take it out in 2wd and turn doung figure 8's on pavement for a while then draining and refilling the transfet case fluid again.
The wife's jeep is starting to do this again. I went to the jeep dealer to get quadratrac fluid and they would not sell it to me saying the new 7176 ATF from mopar is what needs to be in it. Thinking they were wrong I tried it. It is not the right fluid for the viscious in the transfer case, believe me. It did not cure the problem. Next time I go in to get fluid I am not telling what it is for and getting what I want. It will cure the problem with the right fluid in it.
We have pulled a two place trailer with heavy longtracked thundercats on the trailer a lot of time and even my 4 place open trailer. Had to be carefull on the mountain with the 4 place as far as braking needs to be anticipated. Also when I raced Legends cars, I had a semi enclosed trailer we pulled for trips that races were around 100 miles away. Pulled it with the Jeep. The car alone weighed 1100 lbs and the front of the trailer was packed in it's enclosure with tool boxes, jacks, fuel, spare tires, parts and so forth. Jeep pulled it great.
We run the Quaker semi-synthetic oil in it and it has over 250,000 miles on it now. At 60,000 miles it had new pistons put in it under a jeep warranty piston recall
This is about all the issues we have had with the unit chassis wise. They are known for breaking wiring where the doors open (inside the big wire harness rubber boot) so the power windows quit working. I soldered in a short piece of wire in each wire there to keep down the flex so the wires don't break again so soon. Also known for rear wiper motors going out. If you need one of those I have 2 spares.
Hope this info helps, air filter and oil changes and go.... good unit.
----- Gimpster -----