Sierra 18-9410-4 Full Synthetic Engine Oil SAE 30, 5 Quart

Full synthetic SAE 30 marine engine oil in a 5 quart jug, blended for four stroke marine engines that run under constant load at sustained RPM. That duty cycle is the reason marine oil exists as a separate category: an automotive oil spends its life at part throttle, and a marine engine spends its life near wide open with no cooling airflow over the pan.

• Synthetic base stocks hold viscosity at wide open throttle and resist breakdown when the engine runs hot.
• Additive package formulated to exceed FC-W requirements, with API CF/SL service classification.
• Recommended for gasoline and diesel inboard and sterndrive engines.
• Protection through startup, operation and storage, which matters on an engine that sits for months between seasons.
• 5 quart jug, the common oil change quantity for a small block sterndrive.

Check your engine manual for the specified viscosity before you pour. SAE 30 is correct for many marine four strokes and wrong for others.