I agree, the 4.0 is a rock engine, especially the way the fire dept. would have maintained it. I have had 2 XJs and the wife is an 04 WJ right now. All have been stock, except for the one XJ. All ran good and it any small issues came up, a forum search would yield a ton of info for me to do the repairs. Parts are pretty reasonable in my experience. I can tell you this, based on helping a friend work on his Tacoma years ago, those parts are way more expensive than Jeep parts.