How many of us are there? Owners of Dodge based RV's?

Ok eyeteeth, still don't know if it's a circulation issue or heat transfer. When its overtemp feel lower rad hose, if its burning hot, I would pull water pump. If its just warm 100 -120 (like tap water. Radiator is dropping restricted amount of coolant temp, but not enough volume to keep temp down. Replace radiator.