Mercury – 25W-40 Synthetic Blend Marine Oil, 1 Qt. | Lubrication | 92-8M0078622

Overview

Four-stroke marine engines don’t live an easy life. They idle forever, then jump straight into hard throttle, all while dealing with heat, humidity, and salt air. That’s why the oil you run really matters. This 25W-40 synthetic blend is the kind of oil most mechanics keep on the bench—it hangs onto internal parts, stays stable when the engine gets hot, and gives the motor a smoother, easier feel. If you want your outboard or sterndrive to stay healthy for the long haul, clean oil like this is the foundation.

Key Features

 • Made for 4-Stroke Marine Use – Works in both outboards and sterndrives.
 • Synthetic Blend Formula – Helps fight corrosion and everyday wear.
 • Holds Viscosity Under Load – Stays consistent during long runs and hot weather.
 • 25W-40 Weight – The viscosity Mercury designed many of their motors around.
 • 1-Quart Bottle – Easy to store for mid-season top-offs.

Engine & Boat Compatibility

 • 4-stroke outboards
 • 4-stroke sterndrives
 • FC-W rated systems
 • FC-W catalyst-compatible engines

Performance & Practical Benefits

You’ll usually notice the engine sounding smoother after an oil change with this blend. Cold starts settle in quicker, and the motor hangs onto its power better during long days on the water because the oil doesn’t thin out when things heat up. It also helps keep the internals cleaner, which means fewer surprises later.

Why Buy OEM

Mercury blends this oil for the specific stresses their engines face—moisture, long idle times, sudden throttle swings, and heat that just doesn’t quit. Automotive oils aren’t made for that. With OEM, you know the oil will protect the engine exactly the way Mercury intended.

FAQ

Q1: How often should I change my oil?
A: Most boaters do it every season or as soon as they hit their recommended service hours.

Q2: Can this be mixed with other oils?
A: Best to stick with one type and weight to keep protection consistent.

Q3: Is this safe for saltwater use?
A: Yes—its corrosion inhibitors are designed for salt and humidity.

Q4: Does this help cold starts?
A: It does—the synthetic blend clings better, so the engine isn’t starting dry.

Q5: Why not run regular car oil?
A: Marine engines deal with loads and moisture that car engines never see. Car oil breaks down faster in those conditions.