1. Increased airflow at higher speeds: When you drive at 70 mph, there is more airflow over the car's radiator than there is when you drive at 75 mph. This helps to keep the engine cool. At higher speeds, the airflow is reduced, which can cause the engine to overheat.
2. Increased engine load at higher speeds: When you drive at 75 mph, your engine is working harder than it does when you drive at 70 mph. This puts more stress on the engine and can cause it to generate more heat.
3. Faulty cooling system: If your car's cooling system is not working properly, it may not be able to keep the engine cool at higher speeds. This could be due to a number of problems, such as a low coolant level, a faulty thermostat, or a damaged radiator.
If your car is overheating when you drive at 75 mph, you should take it to a mechanic to have it inspected. The mechanic can diagnose the problem and recommend the necessary repairs.
