What oil do you use in a 1979 El Camino?

For a 1979 El Camino, it's generally recommended to use a high-quality motor oil with a viscosity of 10W-30 or 10W-40, depending on the climate and driving conditions. Look for oil that meets or exceeds the API (American Petroleum Institute) standards for that era, which would typically be SN or higher. If the engine has high mileage, consider using a high-mileage formula for better performance. Always check the owner's manual for specific recommendations.