Interesting reading about your radiator problems. I have no overheating problems in any of the 5 XJ's in the family. They all get preventive maintenance. I use the clutch fan from the GC like many others. I usually use a 70/30 mix of prestone and distilled water. I did not notice much discussion about coolant used. Maybe it makes no difference to you guys in Texas. I replaced the radiators in the 01's because of leaks after about 14 years of service. I went with the Spectra from Autozone. I went with them because they had one, and it had a lifetime warrant. Both have been in now over 6 months with no problems. I have no big lifts on the jeeps in the family and nothing blocking cooling flow. Do XJ's in your area that are not lifted have the same cooling problems?