Have you checked the Coolant levels?
headgasket,radiator internal blockage,radiator external blockage, fan not working properly,low coolant,water pump internally wore, loose serpetine belt
or bad thermostat
My problem was a missing air deflector under the radiator. Sounds funny, but it means a lot on all Ford V8's. (See picture.)
most people dont even know the purpose and take em off or rip em off on curbs. congrats on the easy fix though
i change termostat the temperature is high again!!
Easy way to tell since you replaced the thermostat already. Open the radiator cap and start the car . If you see the water or coolant circulating then you can eliminate the pump and hoses from being the problem. Let me know what you find out and we can go from there.
Radiator size?? hoses crimped?
Check to see the electric fan is running if you are running hot in the city. If you run hot on the highway I suggest starting with a pressure test. If that is good i would try a new radiator of have yours re-cored
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