Understanding the New API SQ Category

As automakers continue their quest for better fuel economy and lower emissions from passenger cars, new types of engine oils are needed to better protect today’s smaller, precision-designed engine componenets. That is why, as of March 31, there’s a new engine oil category on the market: API SQ.

The American Petroleum Institute (API) is the leading trade association and standard-setting body for the petroleum industry. Its lubricant standards are developed through a rigorous accreditation process covering performance, safety, reliability, and environmental impact. First announced at the June 2024 meeting of API’s Lubricants Group, API SQ builds upon and enhances the performance and protection attributes of the previous API SP standard.

API SQ Performance Requirements

Gasoline-powered engine technology has evolved rapidly in recent years towards more compact, highly-efficient design to meet increasingly stringent fuel efficiency and emission requirements. As a result, modern engines have different needs from previous generations. Oils formulated to the API SQ standard are intended to address a number of issues, including:

• Enhanced fuel economy: Friction within an engine is a major factor in energy consumption. Advanced lubrication can help reduce friction and improve fuel efficiency.
• LSPI Protection: Low-speed pre-ignition refers to a spontaneous, premature combustion that can occur in turbocharged engines, resulting in engine “knocking” and potentially serious damage. API SQ oils will be formulated to mitigate this risk.
• Improved engine cleanliness: New engine oils are designed to keep engine components cleaner, which improves engine performance and longevity.
• Increased durability: API SQ oils are intended to provide improved protection against wear, extending the life of critical engine parts such as timing chains.
• Regulatory standards: API SQ lubricants will align with current industry and environmental regulations.

What’s new and different?

API SQ represents significantly enhanced protection features relative to its predecessor, API SP. The certification process entailed updates and improvements to the engine testing sequences used to evaluate lubricant performance, including:

• Sequence IIH, used to measure high-temperature viscosity increases and deposit levels.
• Sequence VH, which measures an oil’s ability to control low-temperature engine deposits.
• Sequence VI, which evaluates an oil’s fuel economy benefit.

API SQ oils exceed API SP performance on all these measurers. In addition, the new category paves the way for the introduction of ultra-low viscosity oils such as SAE 0W-8 and SAE 0W-12.

API SQ also calls for a maximum sulfated ash content limit of 0.9%, comparable to API SP but lower than previous generations. Sulfated ash in engine oils is the underlying cause of unburned metallic residue typically resulting from engine oil additives. Ash accumulation can clog gasoline particulate filters (GPFs) that are critical to emission controls. A lower ash level means that emission control systems can function properly and have a longer service life, while car owners can avoid costly maintenance to clean or repair GPFs.

The release of API SQ coincides with the introduction of the ILSAC GF-7 standards, developed by the International Lubricants Standardization and Approval Committee. API and ILSAC standards are generally in close alignment, and that is the case with API SQ and GF-7. API SQ, however, will address ultra-low viscosity grades that are not covered by the GF-7 standard. Both GF-7 and API SQ oils will be backwards compatible for vehicles using GF-6 and API SP oils.

Passenger car drivers will see a number of benefits from these new oil categories, notably better engine performance and lower risk of wear, which helps reduce maintenance costs and extend vehicle life. They should also see some fuel economy improvement. Consumers may not think about how their emission control systems are working until they experience a problem, but those systems will function more smoothly with API SQ oils, meaning fewer carbon emissions into the air.

In keeping with our commitment to bring our customers the advantages of the latest engine oil technology, Chevron is launching new Havoline^® brand ILSAC GF-7 and API SQ passenger car motor oils, which will be upgrades of our existing GF-6 line. Watch this space for more details in the near future.