Make sure that you are not losing coolant into your oil. I doubt it, but double check. This is a common problem with Jeeps. Sometimes the leak will be small and go on for years and sometimes it rips the plastic radiator apart. The stop leak stuff can plug the radiator or heater core so I am not a fan of that product. You can change out the radiator or continue to watch the coolant. Just remember that if it is leaking the day may come where it will leave you stranded. I would just change out the radiator, but that is just me. Stick to a OEM radiator or an all metal one. The cheap ones from Autozone are not OEM radiators and have been prone to go out even with their lifetime warranty. Save your self money and time and just change it out once.
2000 Sahara, 3.5" Rubicon Express Lift, 1" spring spacer & 1" Body Lift, 33" or 35" BFG Mud tires, Front & Rear ARB, Rancho 9000 shocks, UCF Ultra High Belly Up