However, some general guidelines apply:
* For gasoline engines: A conventional oil with a viscosity of 5W-30 or 10W-30 is generally recommended, especially for warmer climates. In colder climates, 5W-30 might be preferable. Check your owner's manual for specifics. Modern, higher-quality oils (synthetic blends or full synthetics) are also perfectly acceptable and often preferred for their extended drain intervals and better performance at both high and low temperatures.
* For the 7.3L Power Stroke diesel engine: This engine typically requires a heavier-duty oil designed for diesel engines. Consult your owner's manual for the specific viscosity and oil type recommended (likely a CJ-4 or earlier specification). These usually have a higher viscosity like 15W-40. Using the incorrect oil can severely damage this engine.
Crucially, always consult your owner's manual. It will specify the exact oil type, viscosity, and API certification your specific 1997 Ford E-350 engine requires. This information is essential to ensure proper engine lubrication and longevity.
