What is api certified oil?

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API certified oil refers to lubricants that meet the standards set by the American Petroleum Institute (API). The API is a trade association that represents the oil and natural gas industry in the United States. Their certification program ensures that oils meet specific performance and quality requirements, providing consumers with confidence in the products they purchase. In this article, we will explore what it means for an oil to be API certified and why it is important for various industries.

What is API Certification?

API certification is a voluntary program that evaluates and certifies lubricants based on a set of industry standards. These standards are developed and maintained by the API’s Lubricants Group, which consists of representatives from oil companies, additive suppliers, and equipment manufacturers. The certification process involves rigorous testing and evaluation to ensure that the oil meets the performance requirements specified by the API.

Why is API Certification Important?

Quality Assurance: API certification provides assurance of the quality and performance of lubricants. The certification process involves testing the oil’s viscosity, wear protection, and other important characteristics. By using API certified oils, consumers can be confident that the lubricant will perform as expected and provide the necessary protection for their equipment.

Compatibility: API certified oils are designed to be compatible with a wide range of equipment and machinery. This ensures that the oil will not cause any adverse effects or damage to the equipment it is used in. Using non-certified oils may lead to compatibility issues, resulting in equipment malfunction or failure.

Warranty Compliance: Many equipment manufacturers require the use of API certified oils to maintain warranty coverage. Using non-certified oils may void the warranty, leaving the equipment owner responsible for any repairs or replacements. By using API certified oils, equipment owners can ensure that they comply with the manufacturer’s warranty requirements.

API Certification Categories

API certification is divided into different categories based on the type and application of the oil. The most common categories include:

API Service Categories: These categories are denoted by a two-letter designation, such as API SN, API CK-4, or API FA-4. They indicate the oil’s performance level and suitability for different types of engines or equipment. For example, API SN is designed for gasoline engines, while API CK-4 and API FA-4 are for heavy-duty diesel engines.

API Performance Levels: Within each service category, there are different performance levels that indicate the oil’s ability to meet specific requirements. These levels are denoted by a number, such as API SN Plus or API CK-4/FA-4. The higher the number, the more advanced the performance level.


API certified oil plays a crucial role in ensuring the quality, performance, and compatibility of lubricants used in various industries. By adhering to the standards set by the American Petroleum Institute, these oils provide consumers with confidence in their purchase and help maintain warranty compliance. Whether it’s for automotive engines, industrial machinery, or other applications, API certification is a reliable indicator of a lubricant’s quality and performance.


– American Petroleum Institute: www.api.org
– API Certification Programs: www.api.org/certification-programs