I just entered the world of jeep ownership and I'm looking forward to being a part of the community. I picked up a manual 99 XJ sport with 130k miles and the 4.0 I6. I was wondering if anyone had any advice as to things I should replace or watch out for. Just looking to make it a reliable DD at this point and then I'll start working on the upgrades. Is their anything notorious that goes wrong on these?
Welcome to the World of Jeeps, Alex.
The 4.0L is a pretty tough engine. With a little TLC, these things will do 300k without much trouble. Whenever, I purchase a new to me Jeep, I start out by going over it from front to rear, changing fluids, and looking at the condition of belts, hoses, and that type of stuff. Water pumps, radiators, electric fan relay, are very important as 4.0L of approximately your Jeep's age have issue of these failing, then your Jeep over heats and blows a head gasket... I am not an XJ person, but I think you will also want to make sure that you are using gold colored anti freeze, not green colored. If I am wrong, there are Jeepers here that will correct me. Also, the AX-15 (transmission) you will want to use 10W30 motor oil or Redline in it.... not gear oil as gear oil has proven to be the death of the brass synchronizers in the transmission. U-joints in both the front axle shafts and both driveshafts would be something to watch in the next 20k miles. If you do or want to learn to do your own repairs, Jeeps are great vehicles for this as there are tons and tons of write ups on the web that include lots of photos and step by step instructions. Stu Olsen Jeeps ( http://www.stu-offroad.com/index.asp
) has a great site that provides 100's of these write ups. Even though a lot of them are written with the Wrangler as the subject, the process is usually the same for the XJ (Cherokee) as the same axles, transmissions, engines, etc. were typically used in both the XJ and the Wrangler. Of course, their is a years and years worth of information about the XJ on this forum as well.