What if the engine overheats while at high speeds on the freeway?
Again, airflow and coolant circulation are crucial. At 55 MPH we can assume you have ample airflow across the radiator, so proper antifreeze circulation is the thing to inspect. I compare overheating at 55MPH to jogging with a sock in your mouth. The faster and longer you jog, the more air you are going to require, and with a sock in your mouth you are going to have to breath extra hard to maintain the proper amount of air to keep you going. At 55MPH the water pump is pumping a large amount of hot antifreeze throughout the cooling system. If there is a restriction in the system like a kinked radiator hose, a restricted radiator, or a stuck thermostat, it will produce the same affect as the sock in the mouth scenario. Rust and water calcification can accumulate in the radiator and drastically reduce the flow of coolant at high speeds. Removing the radiator from the vehicle for disassembly and cleaning or radiator replacement are the only two real cures for a clogged radiator. Using a ca