So i own a 2004 KJ and just topped 78000. I do regular oil changes on time but ive heard that with Jeeps and their four wheel drive there is other maintenance that should also be performed such as changing transmission and differential fluid. Ive owned the truck for 2 years and have no idea what the previous owner has done. Any suggestions?

Petrol or Diesel?

If a diesel - change fuel filter at least every 2 years better every year; also think to change the timing and serpentine belts, pulleys and tensioners. Otherwise, how much offroading do you do? Do you tow? If you do a fair bit, probably a good idea to change diff oils - especially if you don't know what the previous owner did. Transmission fluid (ATF+4) and filters in theory are in for the life of the vehicle; in practise (and depending on your mileage and usage) probably a good idea to change them out as well, about now and think about doing it every other year. Some of the Australian guys change them at least every 30-40k miles, but then their conditions can be a bit extreme. Obviously air filter changes yearly, but if you are somewhere dusty, give it a hoovering every few months between changes.

Check universal joints - they do wear over time.

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