Sierra synthetic 4 stroke oil is specially formulated for the demands of stern drive, inboard and high powered outboard engines. The 25W-50 grade oil contains a blend of additives that boosts the corrosion protection and lubrication for the extreme demands of the marine environment.

It has been developed to outperform standard 4-cycle automotive engine oils in marine applications, with excellent detergency, anti-oxidants, anti-wear, and corrosion protection.

The benefits for marine engines include reduced wear of internal components, corrosion protection for internal parts, cleaner pistons, and prevention of ring sticking. Excellent low temperature operating properties. Meets or exceeds quality performance API SJ, CF-4, CH-4. Recommended for use in Mercury, Yamaha, Evinrude, Mercruiser, OMC and Volvo Penta.