Sierra - 10W-30 4 Stroke Outboard Marine Engine Oil - Gallon - 6 Pack - 9420CAT3 Want to know more about how your engine is breaking-in or wearing? Curious about whether or not your oil is doing its job? Want to be ahead of problems that may develop? PartsVu has partnered with Blackstone Laboratories and we are now offering professional oil analysis kits. Results are typically received in a few days via email. Shop now. NMMA FC-W Certified Catalyst Compatible Engine Oils specifically designed to meet the unique requirements of modern 4-stroke recreational engines with or without emission catalyst systems. Approved for all 4 stroke applications including outboard, sterndrive, and inboards. Exceeds all 4 stroke requirements including FC-W and FC-W Cat compatible. Capitalizing on "ZDDP" anti-wear additive technology to prevent phosphorus depletion and extend the emission catalyst life. This bundle contains 6 Gallons. If you are looking for other quantities of 9420CAT3 10W-30 4 Stroke Outb