What are the specific performance requirements of API SP and ILSAC GF-6A standard?

Before answering this question, do you know about these two associations? What are their main focuses?
API (American Petroleum Institute) SP and ILSAC (International Lubricant Standardisation and Approval Committee) GF-6A are both core standards for modern engine oils. The former focuses on engine protection performance, while the latter emphasises fuel economy and environmental compatibility. Together, they meet the demanding requirements of modern engines, such as turbocharging and direct injection.

API：

API SP is the highest grade of gasoline engine oil launched in 2020 (replacing API SN Plus), specifically designed to address the pain points of modern engines (such as turbocharged direct injection/TGDI and hybrid engines), including common issues with TGDI engines, new SEQ X test, SEQ IIIH test, and SEQ IVB test.
Its core purpose is to reduce the risk of LSPI, minimise stretching and wear of the timing chain, extend chain lifespan, prevent engine power loss and increased emissions caused by chain slack, maintain stability at high temperatures, reduce the formation of sludge and varnish deposits, extend oil change intervals, enhance wear protection for components like camshafts and piston rings, and adapt to the high-load, high-speed operating conditions of modern engine.
Additionally, while not a core requirement, API SP mandates that engine oil maintain protective performance while also prioritising fuel economy (e.g., low-viscosity formulations) and compatibility with the latest National VI emission standards' particulate filter (GPF) to minimise the impact of carbon deposits on emissions.

ILSAC：

ILSAC GF-6A is the fuel-efficient standard for gasoline engine oil launched in 2020 (replacing GF-5), with a focus on improving fuel efficiency and environmental performance through tests such as SEQ VIE, SEQ VIF, and SEQ IX. Compared to GF-5, it requires engine oil to improve fuel economy by up to 25%-30%, reduce engine operating resistance to prevent LSPI phenomena in TGDI engines, protect aftertreatment systems, reduce deposit formation on piston tops, maintain combustion chamber cleanliness, extend engine lifespan, and use low-sulphur, low-phosphorus, and low-ash formulations to reduce toxicity to emission control devices such as three-way catalytic converters and GPFs, making it suitable for vehicles meeting National VI emission standards or higher.
Additionally, the oil must remain highly fluid at temperatures below -35°C (e.g., a pour point of ≤-45°C for 0W-20) to ensure lubrication protection during cold starts. At high temperatures (e.g., above 150°C), it must maintain stable viscosity to prevent oil film breakdown.

What is the relationship between API SP and ILSAC?

The two are complementary. GF-6A is an energy-saving extension of API SP (i.e., ‘SP+ energy-saving requirements’), and both must meet each other's core indicators. Motor oils that comply with GF-6A necessarily comply with all API SP requirements. API SP motor oils that need to be labelled GF-6A must additionally pass the GF-6A fuel economy test.

This synergy ensures that engine oil can both protect modern engines and meet environmental protection and energy-saving requirements, making it the mainstream choice for current US, Japanese, and Korean-branded vehicles compliant with National VI emission standards (e.g., 0W-20 engine oils from brands such as Toyota, Honda, and Volkswagen all require API SP+GF-6A certification).
Together, these two standards form the core criteria for modern engine oil. TERZO 0W-20 viscosity engine oil meets both of these standards, achieving the dual objectives of ‘protection + energy efficiency,’ making it suitable for use in National VI-compliant vehicles equipped with turbocharging and direct injection technologie.