Mercury - Quicksilver 10W-40 4-Stroke Marine Engine Oil Mineral Base Protection Premium Marine Lubrication 8M0148476. Overview. When you spend your weekends on the water, you learn quickly that a reliable engine is more than machinery - it's your ticket to quiet coves, early morning fishing runs and long afternoons with the family. That reliability starts with the oil you trust. The Mercury Marine part number 8M0148476, Quicksilver 10W-40 4-Stroke Marine Engine Oil, gives your motor the steady,