Short answer
ILSAC GF-6B is the part of the GF-6 standard written only for SAE 0W-16 oils, licensed through API from May 1, 2020. It is not backward compatible: it is meant for engines whose manufacturer specifies 0W-16. Oils meeting it carry the API shield rather than the starburst, and ILSAC GF-7B succeeded it in March 2025.
Why 0W-16 needed its own standard
A 0W-16 oil is thinner at operating temperature than a 0W-20. SAE J300 sets its minimum high-temperature high-shear (HTHS) viscosity at 2.3 cP, compared with 2.6 cP for the 20 grade. Engines designed for it have tolerances and oil pumps chosen with that in mind; many older engines were not.
Putting 0W-16 under the existing starburst would have suggested it was suitable wherever an ILSAC oil was called for. Automakers instead created a separate standard so the label itself signals “only where specified.”
What GF-6B tests
GF-6B shares the GF-6 engine test program, including the low-speed pre-ignition and timing chain wear tests, with the same aim of protecting modern turbocharged and direct-injection engines. Fuel economy is measured with the Sequence VIF test, a version suited to the lower viscosity.
The API shield
API created the shield certification mark for GF-6B. API’s rules do not allow the starburst on 0W-16 oils, so a 0W-16 bottle meeting the ILSAC standard shows the shield on the front label, along with the API donut showing the service category and grade.
With GF-7, the shield moved to GF-7B, the 0W-16 standard in the new generation.
Who uses 0W-16
SAE 0W-16 is specified mainly for certain recent gasoline and hybrid models, many from Japanese manufacturers. The owner’s manual or oil fill cap will say so; if it lists 0W-20, use 0W-20 unless the manufacturer has approved the lighter grade.
Frequently asked questions
Can I put 0W-16 in a car that calls for 0W-20?
Not unless the vehicle manufacturer approves it. GF-6B and GF-7B oils are intended only for engines that specify 0W-16.
Why can’t a 0W-16 oil carry the starburst?
API’s licensing rules reserve the starburst for the backward-compatible ILSAC grades. The shield was created so 0W-16 oils have their own clearly different mark.
General maintenance information. Always follow your vehicle or equipment manufacturer’s requirements and the current product data. Questions? Email [email protected].