Short answer
API SQ is the American Petroleum Institute service category for gasoline engine oils that followed API SP, with licensing beginning March 31, 2025. It launched alongside the automaker standards ILSAC GF-7A and GF-7B. An API SQ oil marked “Resource Conserving” corresponds to ILSAC GF-7A, while plain SQ can be claimed by grades outside the ILSAC range.
Why API introduced SQ
API SQ and ILSAC GF-7 were developed together. The update kept the same family of engine tests used for SP and GF-6 but tightened how several of them are judged, after automakers asked for stronger protection over the full drain interval and better fuel economy from the lighter grades.
Industry technical summaries of the program highlight an added used-oil (aged-oil) evaluation in the low-speed pre-ignition test, tighter fuel economy limits for the ILSAC grades and tighter piston cleanliness limits for GF-7A. The exact limits live in API’s licensing documents.
SQ, SQ Resource Conserving and the ILSAC marks
The donut on an SQ oil shows SQ in the top half and the SAE grade in the center. When the bottom half also reads Resource Conserving, the oil meets the matching ILSAC requirements for its grade. GF-7A covers 0W-20, 5W-20, 0W-30, 5W-30 and 10W-30, and oils meeting it can display the API starburst on the front label.
SAE 0W-16 oils meeting ILSAC GF-7B use the API shield instead of the starburst. Heavier grades such as 0W-40 or 10W-40 can be licensed as API SQ without the Resource Conserving wording.
What SQ means for older vehicles
API’s long-standing guidance is that the newest gasoline category includes the performance of the categories before it. In practice, a manual that calls for API SP, SN or an older S category is normally satisfied by an SQ oil in the viscosity grade the manual specifies.
That backward compatibility applies to the API category. Automaker-specific approvals, European sequences and motorcycle standards are separate, so an SQ donut does not by itself mean an oil carries one of those.
Frequently asked questions
Is API SQ better than API SP?
SQ is the newer category, with requirements set after SP and in some areas tightened. Whether that matters for your engine depends on what the manufacturer specifies; the right choice is the viscosity grade and specification in the owner’s manual.
Do I have to switch to an SQ oil?
No rule requires it. Oils licensed under SP were tested to that category, and the manual is the guide. Newer vehicles may begin listing API SQ or ILSAC GF-7 directly.
General maintenance information. Always follow your vehicle or equipment manufacturer’s requirements and the current product data. Questions? Email [email protected].