ILSAC Standards
Engine Oil & Fluids · 6 specs
Direct Answer
ILSAC GF-6 (developed by the International Lubricant Standardization and Approval Committee of Japanese and American automakers) defines fuel economy, timing chain wear reduction, and engine durability standards. Splitting into GF-6A (backward-compatible for 0W-20, 5W-20, 5W-30, 10W-30) and GF-6B (dedicated to ultra-low viscosity 0W-16 oils).
Source: ILSAC (AAMA & JAMA) Specification GF-6A / GF-6B / API 1509 · Last reviewed Aug 28, 2026
Specs
| Standardization | ILSAC GF-6A / ILSAC GF-6B (Mandated May 2020) |
| ILSAC GF-6A (Starburst Symbol) | Backward compatible with older GF-5 and GF-4 specifications for SAE 0W-20, 5W-20, 0W-30, 5W-30, 10W-30 |
| ILSAC GF-6B (Shield Symbol) | Exclusively for SAE 0W-16 viscosity oils (NOT backward compatible with engines requiring GF-6A / GF-5) |
| Timing Chain Wear Test (Sequence X) | A mandatory ASTM test that limits acceptable timing chain elongation over an extended multi-day cyclic engine run (specific pass/fail thresholds are set by the ASTM Sequence X test procedure, not reproduced here in full) |
| Piston Deposit & Cleanliness (Sequence IIIH) | A high-temperature ASTM oxidation/deposit test that runs the oil under sustained elevated temperature to evaluate resistance to ring sticking and varnish formation (exact duration/temperature are set by the ASTM Sequence IIIH test procedure) |
| Automaker Backing | Alliance of Automobile Manufacturers (Ford, GM, Stellantis) and Japan Automobile Manufacturers Association (Toyota, Honda, Nissan) |
Why GF-6B Has a Different Shield Symbol
Because SAE 0W-16 oil is extremely thin (6.1 to 8.2 cSt at 100°C), using it in an older engine designed for 5W-30 could lead to severe hydrodynamic bearing failure. ILSAC created the new API Shield logo specifically for GF-6B containers to prevent consumers from accidentally pouring 0W-16 into incompatible engines.