Originally Posted By: Quattro Pete
Originally Posted By: dave07
Straight from my owners manual: "Use of synthetic or synthetic blend motor oil is not mandatory. Engine oil need only meet the requirements of Ford specification WSS-M2C945-A and display the API Certification Mark.
Amsoil meets this spec and is of the right viscosity.
Read again what Trav posted. Amsoil does not meet this spec. It is only "recommended for." Amsoil SS 5w-20 oil also does not display API Certification Mark.
If the API would treat all base lubricants fairly, Amsoil Signature Series would be API SN certified just like their XL and OE formulations. However, the API is heavily biased on group II and group III base oil formulations, allowing base stock swapping with minimal re-certification documentation.
We all know this rule does not apply to group IV and V base oil formulation, requiring a complete redo (money as well) of the entire certification process. Therefore, if one supplier is not able to meet demand, Amsoil can't go to another suppler of the exact same quality of material to continue production without a new certification process.
Until base oils are treated equal and fairly, Amsoil will never pay for the certification process from the API, despite exceeding the quality and formulation requirements to pass. Besides, the API is a minimum certification benchmark and hardly insures top tier quality.
Originally Posted By: dave07
Straight from my owners manual: "Use of synthetic or synthetic blend motor oil is not mandatory. Engine oil need only meet the requirements of Ford specification WSS-M2C945-A and display the API Certification Mark.
Amsoil meets this spec and is of the right viscosity.
Read again what Trav posted. Amsoil does not meet this spec. It is only "recommended for." Amsoil SS 5w-20 oil also does not display API Certification Mark.
If the API would treat all base lubricants fairly, Amsoil Signature Series would be API SN certified just like their XL and OE formulations. However, the API is heavily biased on group II and group III base oil formulations, allowing base stock swapping with minimal re-certification documentation.
We all know this rule does not apply to group IV and V base oil formulation, requiring a complete redo (money as well) of the entire certification process. Therefore, if one supplier is not able to meet demand, Amsoil can't go to another suppler of the exact same quality of material to continue production without a new certification process.
Until base oils are treated equal and fairly, Amsoil will never pay for the certification process from the API, despite exceeding the quality and formulation requirements to pass. Besides, the API is a minimum certification benchmark and hardly insures top tier quality.