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Mercury 25W-40 4-Stroke Synthetic Blend Marine Engine Oil, 1 Gallon - 8M0078630

Based on 719 reviews
Condition: New
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$63.99

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This item's return window has been extended for the holiday season: Returnable until Jan 31, 2027

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Availability: In Stock.
Fulfilled by LEADERS RPM

Arrives Saturday, Nov 21
Order within 14 hours and 38 minutes

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At a glance

Condition
New
Model
8M0078630
Weight
16 oz
Liquid Volume
1 gal
Package Information
Bottle
Vehicle Service Type
Marine Engines
Flash Point
400 °F
In the box
Engine Oil

Features 6

  • For use in Mercury, MerCruiser and other leading brands of four-stroke outboard, sterndrive and inboard marine engines
  • Provides outstanding wear and corrosion protection to help extend engine life
  • Maintains viscosity, protects against varnish buildup and sludge formation, and exceeds the rust protection requirements for NMMA certification
  • Outperforms automotive oils in marine applications thanks to its specialized additive package designed for the rigors of the marine environment

Description

Give your hard-working outboard, sterndrive or inboard engine the protection it deserves with Mercury SAE 25W-40 Synthetic Blend 4-Stroke Marine Engine Oil 8M0078630. Unlike automotive oils, Mercury Marine Engine Oils are specially formulated for the unique needs of life on the water. An advanced additive package includes superior corrosion inhibitors to help protect your engine in damp, humid environments and during storage. This premium synthetic blend formula offers powerful viscosity retention and shear resistance to prevent wear even during periods of hard operation. It exceeds all marine industry requirements for 4-stroke oil and is certified FC-W and FC-W Catalyst Compatbile. Use it in any 4-stroke marine engine that calls for 25W-40 oil.

Specs 18

Brand MERCURY
Liquid Volume 1 gallons
Package Information Bottle
Vehicle Service Type Marine Engines
Flash Point 400 °F
Brand Name MERCURY
Manufacturer Part Number 8M0078630
UPC 745061915701

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Nov 21

Yes, absolutely! This item's return window has been extended for the holiday season: Returnable until Jan 31, 2027.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews


Good purchase
Good oil
Reviewed in the United States on April 4, 2026 by Dave

Good product.
Great looking watch and feels like a very expensive one as well.
Reviewed in the United States on September 29, 2025 by Matt

Good
Good oil
Reviewed in the United States on October 11, 2025 by Tyler

just as advertised
just as advertised
Reviewed in the United States on March 29, 2026 by Captain Pete

Exactely As Ordered
Merc oil was received in great shape and properly sealed, no leaks. Oil is the same as Quicksilver and less expensive, plus is recomended by Merc. Good price and fast ship. Cannot beat Prime.
Reviewed in the United States on February 27, 2025 by Amazon Customer

Good Stuff
Used in Volvo 280 SP outdrive !
Reviewed in the United States on June 11, 2025 by Thomas L

Good product
Good price
Reviewed in the United States on September 4, 2024 by Stephen Stamps

on time
goog value
Reviewed in the United States on November 21, 2025 by robert thomas
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