Get the VIN and call a dealership to see if the Service Campaign (it is not a recall) was done on the head gaskets. Some places are still doing them so I have been told. 3.0 are not the easiest engines to work on. Low on power,4:70 dual cases fix that but cost more. Bad MPG, I have a 16 gallon cell mounted where the spare for a holding tank.
My rig works awesome on the trail, but there is a lot of work and money tied up in it. I have owned it since 97 and been wheeling it since I got it with no problems. If I were to do it today, I would look for a 5-speed 22r because they are simple to work on.