I have only owned the jeep about a month and a half it has 100k (98) thats all I know about the history. It has a clicking noise (in 2WD) that starts at about 15 and at about 30 you dont hear it any more,probably because of road noise.
When you put it into 4WD and press the gas there is a clanking, grinding noise. It almost sounds like when your riding a bycycle, you pedal and the chain slips .I raised the front and turned the wheel with a quick motion while it was in 4WD .When I did it made the same noise but when I turned the wheel in a slower motion it made the clicking noise I hear when Im driving in 2WD.
The history like I said is very limited my friend sold it to me (he gets confused by a screwdriver).