First be sure the radiator fan is turning on. If it is not, the engine will not over heat at highway speeds when natural air flow is sufficient. Next, have your mechanic perform a chemical test at the radiator for a leaking cylinder head gasket. That just takes a few minutes. Usually if a head gasket is leaking, you'll be losing coolant too over time.
Sunday, May 7th, 2017 AT 5:48 PM