However, generally speaking, for either engine, you'll want to use:
* SAE 5W-30: This is a common and widely recommended viscosity for most conditions. Check your owner's manual, as 10W-30 might also be acceptable depending on your climate.
* API certified oil: Look for the API certification symbol (a "donut" shaped symbol) on the oil container. This ensures the oil meets certain quality standards. For older vehicles like a '97 Expedition, an API rating of SN or higher is recommended. SM is acceptable if SN isn't available.
* Oil type: Conventional, synthetic blend, or full synthetic oil can all be used, again check your owner's manual for recommendations. Full synthetic oil offers better protection and longer life, but costs more. Synthetic blends offer a good compromise.
Before you change your oil: Consult your owner's manual. It will specify the exact type and amount of oil your specific Expedition requires. Ignoring this could damage your engine.
