If still a problem then i d change out the radiator.
Jeep wrangler fan clutch test.
1 check for oil streaks or dust collected on oil streaks on the fan clutch it s a sure sign that the internal fluid that provides the clutch action is leaking.
2 check for a worn bearing.
2 check for a worn bearing grasp the fan blade on either end with the engine off and check for lateral movement.
It would need to be far more worn before you would notice it doing that test.
I m sure a lot of people will disagree with me on this but if it was my jeep i would just go ahead and replace the water pump thermostat and fan clutch and see where you are at that point.
The fan clutch is not an expensive part and it is difficult to test.
When it begins to fail you will notice it heating up at idle but it will pass the spin test you mentioned.
This shows how to replace and install a fan clutch using test mule jeep wrangle.
How to tell if a fan clutch is defective.
If you are doing the work yourself all of the above will be well under 500.
It s a sure sign that the internal fluid that provides the clutch action is leaking.