Well, how many miles are on your jeep? It kinda matters, mine has 185k and i just changed the t stat; the fluid was a bright clean green but the t stat housing had a ton of scale and crap inside.The stuff in my housing had to be scraped out and imo would never come out with a flush. My jeep also overheats only with the a/c on, so i looked inside the rad with the engine running and it had no flow til i revved the motor. I'm thinkin caked up rad or bad water pump.

 

Jeep cooling systems suck period. Either get a new radiator or wire ur electric fan to be on all the time. Do the fan first cuz thats super cheap if u know how to run wires. After a radiator swap u could take it a step further and mount custom dual electric fans which would keep it cool for sure.