Guide to Mercury Marine Precision Oils & Lubricants

Boating is not often thought of as a harsh environment, but in fact it is one of the most demanding environments in which an engine can operate.

Marine engines can and are often used for extended periods at wide-open throttle (up to 6400 rpm on some models), in harsh saltwater, and intense UV sunlight. Then, marine engines sit in storage over the off-season, in many cases without any use.Focusing on these demands, all Mercury Marine Precision Oils and Lubricants are specially engineered for the unique needs of marine engines and rigorously tested to meet our high standards, protecting your outboard and providing many years of engine life.


Mercury Precision Lubricants

2-Stroke Marine Oil


Premium Plus 2-Stroke High-Horsepower Outboard Oil

Specifically formulated with a higher concentration marine additive package to meet the needs of high-horsepower Mercury Precision Lubricants 2-Cycle Outboard Oiloutboards including direct fuel-injected engines in extreme marine operating conditions. Far exceeds Mercury in-house test standards, which are more stringent than the industry’s TC-W3 standard. Cleanest burning, reduces carbon build-up in exhaust system and superior lubrication. Meets all outboard and personal watercraft manufacturers’ recommendations for use of TC-W2 and TC-W3 oils in pre-mix or oil-injected 2-cycle applications. Provides warranty protection for Mercury, Mariner, Force and Sport Jet and M2 Jet Drive 2-cycle engines.

Available container sizes:

Pint – 92-858025K01

Quart – 92-858026K01

Gallon – 92-858027K01

2.5 Gallon – 92-858028K01

Savings – 3 Gallon Multipack


OptiMax/DFI 2-Stroke Outboard Oil

A synthetic blend 2-Cycle engine oil specifically formulated and developed to meet the needs of OptiMax and Direct Fuel Injected (DFI) 2-cycle outboard engines.  Provides the maximum protection for OptiMax and DFI engines even under the most extreme operating conditions. Outperforms other oils by combining a carefully modified base stock blend with a synthetic additive package. Minimizes carbon build-up to help maintain engine top end speed and acceleration. Superior lubrication for increased resistance to piston scuffing. Will mix with typical 2-cycle engine oils. Provides warranty protection for Mercury and Mariner OptiMax and DFI outboards.

Available container sizes: DFI OptiMax 3-Pack.jpg

Gallon – 92-858037K01

2.5 Gallon – 92-858038K01

Savings – 3 Gallon Multipack


Premium 2-Cycle Outboard Oil for Low to Mid-Horsepower Outboards

Specifically formulated with a marine additive package to meet the needs of low-to mid-horsepower outboard engines operating under general marine conditions. Exceeds TC-W3 standards. Reduces rust and corrosion of internal components. Meets all outboard and personal watercraft manufacturers’ recommendations for use of TC-W2 and TC-W3 oils in pre-mix or oil-injected 2-cycle applications. Provides warranty protection for Mercury, Mariner, Force and Sport Jet 2-cycle engines.

Available container sizes:

Pint – 92-858020K01

Quart – 92-858021K01

Gallon – 92-858022K01

2.5 Gallon – 92-858023K01


Mercury Precision Lubricants

4-Stroke Marine Oil

FC-W 4-Stroke (25W-40) Oil

Mercury’s 4-stroke oil technology outperforms automotive oils in marine applications because of its specialized additive package designed for marine engines. 25W40 is recommended for all marine engines.

Things to know about this oil:9-9ProKicker_NitroLifstyle_4.jpg

  • For use in all 4-stroke marine engines. This oil is engineering approved for all marine 4-stroke applications including: outboard, MerCruiser, high performance, stern drive/inboard. Exceeds all marine industry 4-stroke oil requirements including FC-W and FC-W compatibility.
  • Outstanding engine and corrosion protection – industry leading strength and viscosity retention and ultimate corrosion and wear protection.
  • The most recommended marine oil. More than 5 years of development work by the largest marine manufacturer in the world.

Available container sizes:

Quart – 92-8M0078627

Gallon – 92-8M0078628

Synthetic Blend 4-Stroke (25W-40) Outboard Oil

A technology specific 25W-40 marine oil formulated for the world’s first and only supercharged and intercooled outboard engine. The unmatched torque and acceleration of the Mercury Verado engine requires maximum protection found in this well-balanced combination of today’s highest quality synthetic and mineral base stocks. Mercury 25W-40 Synthetic Blend Outboard Oil meets the stringent marine operational requirements of all of Mercury’s new 4 and 6 cylinder models. First in class for all FC-W durability test properties with industry leading internal Marine engine corrosion protection.

115-ProXS_FS_FreshWater_LakeButteDesMorts-2.jpg25W-40 Synthetic Blend Oil shows significantly better shear stability and volatility, and is higher in viscosity and High Temperature High Shear (HTHS) after shear. The popular competitive formulation uses a fair amount of VM (viscosity modifier) which is subject to shear, while the Mercury oil contains no VM. As a result, the Mercury oil will hold its viscosity far better in high-revving and long-running situations when the engine needs it most. The HTHS after shear follows along with the viscosity stability, which also results in improved bearing protection.

Available container sizes: 

Quart – 92-8M0078629

Gallon – 92-8M0078630


4-Stroke (10W-30) Outboard Oil

Specifically formulated and developed to meet the needs of all 4-stroke outboard engines. Developed for the rigors of the marine environment. Industry-leading corrosion protection. Features premium-grade synthetic and mineral-based stocks with specially designed marine grade additives not required in automotive oils. Outstanding lubricity for internal engine components to reduce wear, scuffing and scoring. Excellent running quality and long-term reliability. Rigorously tested to guarantee warranty protection for Mercury and Mariner 4-stroke outboards.

Available container sizes:

Quart – 92-8M0078625

Gallon – 92-8M0078626 

Mercury Precision Lubricants Gear Lube

Premium Gear Lube – Lower Units for Outboards Below 75 Horsepower

Mercury Marine gear lube outperforms automotive gear oil in marine applications because of its specialized additive Mercury Precision Lubricants Premium Gear Lubepackage designed for marine gear cases. Continued use of this gear case lubricant will: Provide maximum protection against excessive wear – even in the presence of water prevent corrosion and pitting. Mercury Premium SAE 80W90 Gear Lube is recommended for lower units for outboards below 75 horsepower. Mercury Premium SAE 80W90 Gear Lube should not be mixed with Mercury High-Performance SAE 90 Gear Lube.

Available container sizes:

8oz Tube – 92-802844K01

Quart – 92-858058K01 

2.5 Gallon – 92-858059K01

High-Performance Gear Lube

Mercury Precision Lubricants Gear LubeEngineered to provide maximum protection for sterndrive and outboard lower units. Exclusive formula is engineered to
provide extended gear life in extreme conditions including high-speed and high-horsepower applications. Extensively tested to provide excellent protection against corrosion and excessive wear. Specifically formulated to help prevent failures due to water entering the gear housing. Extreme pressure synthetic additives protect gears from metal to metal contact. Since no industry-wide standards exist concerning marine gear oils, it is essential to use products such as Mercury High-Performance Gear Lube which has been specifically designed and tested for marine applications. DO NOT mix with Mercury Premium Gear Lube. Provides warranty protection for all Mercury MerCruiser sterndrive and Mercury, Mariner and Force outboard lower units.

Available container sizes:

8oz Tube – 92-802851K01

Quart – 92-858064K01

2.5 Gallon – 92-858065K01

Savings – 6 Quart Multipack

Also Check Out Our Gear Lube Kits





Mercury Precision Lubricants Diesel Engine Oil


Diesel (15W-40) Engine Oil

Specifically formulated and developed to meet the needs of all marine diesel engines, including Mercury MerCruiser D-Tronic. Contains a higher additive level than standard fleet oils, providing greater protection. Provides excellent wear tolerance. Provides excellent shear stability to assure stay-in-grade performance. Protects the internal engine components from corrosion and wear. Helps control the formation of sludge and varnish deposits, even in highly stressed applications. Provides warranty protection for Mercury MerCruiser Diesel engines.

Available container sizes:

Gallon – 92-858042K01



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Topics: General Repair, Care & Maintenance,Marine Products Buying Guides,Mercury Maintenance