AMSOIL Signature Series 100% Synthetic 5W-30 Motor OilA reader asks: AMSOIL recommends Signature Series 5W-30 for my 2012 Ford EcoBoost F-150, but I see online that some forced induction F-150 owners go with AMSOIL Series 3000 5W-30 Heavy Duty Diesel Oil. What is the difference between these oils? Is the Series 3000 5W-30 Diesel Oil not suitable for my truck or is the Signature Series 5W-30 a better product?

Our answer: Your EcoBoost F-150 requires an engine oil bearing the API SN and Ford WSS-M2C946-A specifications, so between those two oils, you must go with the Signature Series 5W-30. Aside from covering numerous diesel engine oil industry specifications, Series 3000 5W-30 Heavy Duty Diesel Oil is designed for the “API SL” spec for passenger car/light truck service. The API SL spec dates back to 2001. Series 3000 Heavy Duty Diesel 5W-30 is a superb product, but it will have higher additive levels of items such as zinc and phosphorus which may not be compatible with the complex emissions components on your truck.

The modernized Signature Series Synthetic 5W-30 uses a different additive balance than the Series 3000 5W-30. Is the Signature Series 5W-30 a better motor oil than Series 3000 5W-30? Both are world-class products and would be considered an elite choice for any appropriate application. The newer Signature Series 5W-30 simply utilizes a newer and more sophisticated approach to motor oil formulation. By the way, because your engine is turbo-charged, stick with the “Severe Service” drain interval as is outlined on the bottle. This would be a maximum of one year or 15,000 miles (24,000 km).

Note that we also offer two other motor oils which are suitable for the F-150 EcoBoost engine. The AMSOIL OE 5W-30 Synthetic Motor Oil and the AMSOIL XL 5W-30 Synthetic Motor Oil are great alternates to the high-end Signature Series product.

For more information, contact us using the form on this page or call us at 1-800-748-5781.