Improved fuel economy and oxidation control
The principal changes in GF-7 are tighter performance demands in Sequence VIE fuel economy and Sequence IIIH oxidation & deposit control. Both changes are designed to help the OEMs meet the challenges of future EPA emissions targets and ensure that engines have minimal energy losses due to viscosity or friction while simultaneously enabling newer engine designs to operate at even greater levels of combustion efficiency and increasing the thermal stress on the oil. Although other industry participants believe these performance targets cannot be adjusted concurrently, a review of previous ILSAC category changes highlighted in the spider chart below indicates that since ILSAC GF-3, fuel economy, and engine oil robustness have consistently increased together.