How can you tell if you have a blown head gasket in a 2003 Ford Explorer if no water is in the oil

Water in the oil is not the only symptom of a blown head gasket. You can have a blown gasket where the cylinder gasses are being injected into the the water jacket only. This will overpressurize and overheat the engine. There is a test that can detect this using a coolant sample from the radiator to test for hydrocarbons present in exhaust. Lastly, the gasket can blow to the exterior of the engine, allowing compression gasses to escape the engine block. The quickest DIY test to determine the possibility of a blown gasket is a cylinder compression test. The compression should be approximately the same in all cylinders and should not leak down quickly. If it does, this indicates either a blown head gasket or possible valve issues.