That Golden Oil
Shortly after acquiring my first prewar car, I discovered an intense debate over oil, detergent or non detergent that was and till is the question. All the good folks that I've talked to, all had their opinions concerning this question. But what about Quality! Oils have to perform a pretty though job, so how can we know what an oil is designed to do before we put it in our car, So I did some research and here's what I found.
The API Service ratings set a minimum standard for oil performance and are updated as engine technology places higher demands on motor oils. These API Service Classifications are only minimal standards and there are performance variations between brand names, but as a general rule the higher the rating, the better job the oil will be able to perform. The following is a brief summary for each API Classification.
SA: It's Oil.
SB: For Minimum Duty Gasoline Engines. Intended for engines operating under conditions mild enough to require only minimum protection. The key word here is "minimum"
SE: For 1972 Gasoline Engine Warranty Maintenance Service: Service typical of gasoline engines in cars and some trucks beginning with 1972. Oils designed for this service provide more protection against oil oxidation, high temperature engine deposits, rust and corrosion in gasoline engines than oils which are satisfactory for API Engine Service Classifications SD or SC.
SF: For 1980 Gasoline Engine Warranty Maintenance Service: Service typical of gasoline engines in cars and some trucks beginning with 1980. These oils provide increased oxidation stability and improved anti wear performance for autos which require API Engine Service Classification SE. They also provide protection against engine deposits, rust and corrosion.
SG: For 1989 Gasoline Engine Warranty Maintenance Service: Service typical of gasoline engines in cars and some trucks. Oils designed for this service provide greater resistance to sludge, varnish buildup, oxidation and wear. These oils provide more protection for your engine than oils satisfactory for API Engine Service Classification SF and SE.
SH: For 1993 Gasoline Engine Warrant Maintenance Service: This category of oils are required to meet tougher testing standards than previous service ratings. API SH engine significantly improve engine cleanliness and durability. SH motor oils are required for use in engines manufactured since 1993. In addition they provide better fuel economy and protection for older cars.
SJ: For 1997 Gasoline Engine Warranty Maintenance Service: I don't know what this is suppose to improve, guess I'll have get back to you on this one, but it has already started to appear on store shelves.
A word about Non Detergent oils; The best API Rating for a non detergent oil that I have been able to find locally has a SB rating.
Webmaster: This artcile is over ten years old, but I hope it will give you an idea of what goes into modern motor oils.