Decoding Symbols on Oil Bottles: What Do API SN/CF, ACEA A3/B4 Mean?

ARTICLE CONTENT

Introduction: Don't Let the "Matrix" of Parameters Fool You

When you hold a bottle of engine oil in your hand, what do you see? Most of us only care about the viscosity level (e.g. 5W30, 10W40) and the brand. But the real "soul" of the oil bottle lies in the small letters, a "matrix" of symbols such as API SN/CF, ACEA A3/B4...

These are not meaningless characters. They areperformance standardsOils must pass a series of rigorous tests to determine whether they are qualified to protect your engine. Using the wrong grade, even if the viscosity is correct, can cause serious damage to your engine.

This article will help you "decode" it all, so you can confidently choose the best oil for your car.

1. API Standards - "Birth Certificate" From the American Petroleum Institute

API (American Petroleum Institute)is the most common standard, established by the American Petroleum Institute. It classifies motor oils based on performance and engine type.

API symbols are usually in the formAPI S_ / C_.

Decoding the symbol "S" (Service - For Gasoline engines):

The letter "S" (Spark Ignition) indicates oil for gasoline engines.

The letter following the "S" represents the performance level. The further down the alphabet, the higher and newer the grade (e.g. SN > SM > SL). Higher grade oils can be substituted for lower grade oils, but not vice versa.

SL (2004):Old standard, used for vehicles 2004 and earlier.

SM (2010):Improved anti-oxidation and anti-scaling properties.

SN (2020):Better piston protection at high temperatures, sludge control and seal compatibility. This is a very high standard and is common today.

SP (Latest):Introduced in 2020, designed to combat low speed pre-ignition (LSPI) in newer GDI Turbo engines.

Decoding the symbol "C" (Commercial - For Diesel engines):

The letter "C" (Compression Ignition) indicates oil for Diesel engines.

Similar to gasoline engines, the letter and number following it represent the efficiency level (e.g. CF, CH-4, CI-4, CK-4).

CF (1994):Old standard for diesel engines without turbo.

CF-4, CH-4, CI-4:For heavy duty, turbocharged diesel engines.

CK-4 (Latest):Better protection against wear, oxidation, durability at high temperatures.

So what does "API SN/CF" mean?

When you see both of these symbols, it means:

"SN":This is the performance levelmainof oil, meets high SN standards for gasoline engines.

"CF":This oil alsomeetSome basic requirements for Diesel engines (CF class).

Conclude:This oil is primarily intended for new gasoline engines, but can also be used in older diesel engines requiring CF grade.

2. ACEA Standards - Strict "Test" From Europe

ACEA (European Automobile Manufacturers' Association)is the standard of the European Automobile Manufacturers Association (including BMW, Mercedes, VW, ...). The ACEA standard is often considered asmore rigorousAPI, with particular focus on film strength, deposit resistance and compatibility with complex exhaust gas treatment systems.

How to read the ACEA standard:

A/B (Example: A3/B4, A5/B5):For use in Gasoline (A) and Diesel (B) engines in passenger cars (PCMO).

C (Example: C3, C5):For use in petrol and diesel engines with exhaust gas treatment systems (DPF/GPF). This is a "Low SAPS" oil (low ash, phosphorus, sulfur content).

AND:Used for specialized heavy duty diesel engines.

Decoding "ACEA A3/B4":

This is one of the most popular and high performance standards of ACEA:

A3:For high performance gasoline engines, allowing extended oil drain intervals, requiring high oil film strength (HTHS).

B4:Similar to A3 but for Diesel engines (no DPF filter).

Conclusion A3/B4:This is the oilHigh performance, high SAPS content (High SAPS), creates a thick and durable oil film, providing excellent engine protection under severe operating conditions. It is ideal for European engines not equipped with a DPF, butnot usedfor vehicles requiring "Low SAPS" (type C) oil.

3. Why Care? What Are the Consequences of Using the Wrong Oil?

This is extremely important. Assuming your car is a newer Diesel with a particulate filter (DPF):

If you use oilACEA A3/B4(High SAPS) instead ofACEA C3(Low SAPS), the ash content in the oil will makepermanent blockageDPF filter, replacement cost can be up to tens, hundreds of millions of dong.

Gartz - Products That Meet The Highest Standards

Understanding these standards will help you recognize the value of a premium lubricant product. Instead of just listing basic specifications, products like Gartz lubricants clearly state the standards they have passed.

For example, when you look at a bottleGartz SAE 5W30 engine oil, you will find this product meets a series of rigorous standards:

API SN/CF:Meets high US standards for gasoline engines and is compatible with diesel.

ACEA A3/B4:Meets European high performance and durability standards.

ACEA C3:Always meets "Low SAPS" standards for vehicles with catalytic converters.

MB 229.31 (Mercedes), BMW Long Life-04, VW 502/505:Approved by prestigious German car manufacturers.

What does this mean?This means Gartz motor oils are designed to meet and exceed the most stringent protection requirements, ensuring your engine stays clean, runs smoothly and is maximally protected.

Conclude

A bottle of motor oil is more than just a liquid, it's a technology. By understanding symbols like API and ACEA, you're no longer making a blind purchase, but becoming a smart consumer who knows exactly what you're giving your engine's "health" to a worthy product.