The recommended engine oil for a 2003 Ford Explorer Sport depends on the engine it has. There were a few different engines offered that year. To be certain,
check your owner's manual. It will specify the correct type (conventional, synthetic blend, or full synthetic), viscosity (like 5W-20, 5W-30, or 10W-30), and the amount needed.
Failing that, you can usually find this information on a sticker located under the hood, often near the radiator or oil fill cap. Look for something that specifies the type and viscosity of oil recommended for your engine.
Without knowing the specific engine in your 2003 Ford Explorer Sport, I can't give you a definitive answer.
