Re: looking to buy a truck
I've got a 2000 Cherokee that I've had for 10 years. Prior to that I had a 98 Cherokee, before that an 89 Cherokee. All with the 4.0. So let me tell you a thing or two about Cherokees

They are very reliable, not terriffic on gas milage. 15 in town, 19 highway. They will 4 wheel with the best of anything.
There are some notorious but easy things to deal with about them.
1. Oil adapter O rings. There are two very annoying to get at O rings under the oil filter adapter to the block.
2. Leaky valve cover gasket that is often confused with a rear main seal leak
3. Leaky rear main seal. Fortunately it's two piece and can be changed by dropping the pan.
4. Front track bar and steering stabilizer shock. Common at 100,000 miles. When these wear, they result in the dreaded Jeep "death wobble" that starts violently at about 52 mph. The bar is $120 bucks and about an hour and a half to change. The steering stabilizer needs to be replaced with the heaviest duty one you can find, Heco and Rancho work well at about $80, half hour to change.
5. The radiators tend to be crappy at 100,000 miles. I replaced mine with a heavy duty unit from Ebay for $70, about two hours to change.
6. Electric window regulators like to die. Not cheap at $125 each.
7. Even though it's rated to tow 5000 lbs, 2500 is tops in reality given the short wheel base and average brakes.
8. Expect to change brake pads every 40,000. They also like to warp rotors especially if used for towing. There are two different rotors for some reason. If you do need to change one, have your old one in hand to get the correct back spacing. $36.
9. Heater fan resistor. If the fan is either all on or off, you get to change this out. Located in the passenger side kickpanel, $65 from the dealer.
So as you can see, there's several mostly annoying things to keep an eye on. Nothing horribly expensive parts wise. Fortunately repairs are doable for the average guy as they are pretty simple mechanically. Once they are fixed, no worries for another 100,000. I get offers constantly to buy mine but I won't consider selling it. It's a bit of a beater, but when the snow flies, nothing I'd rather be driving.