I have had so many issues with my Jeep XJ and overheating. Everything has been replaced and it is working perfect now. HOWEVER, during my troubleshooting and heating issues, I learned quite a bit during the way. One of the most important steps I learned was... properly flushing the system and using the appropriate radiator fluid to fill the system. Hopefully this helps you along the way and makes it a bit easier for you to flush your system.