Mercury 4-Stroke Oil 4L 8M0078640
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Mercury 4-Stroke Marine Engine Oil β 4L β 8M0078640
Protect your marine engine with Mercury 4-Stroke Marine Engine Oil 8M0078640. This genuine Mercury OEM SAE 25W-40 marine engine oil is specifically formulated for use in Mercury outboards, MerCruiser sterndrives, and other 4-stroke marine engines.
Unlike automotive oils, this marine-specific formula contains an advanced additive package designed to handle the extreme loads, high RPM, and corrosive environments encountered in marine applications. It provides outstanding wear protection, corrosion resistance, and viscosity stability to help extend engine life and maintain peak performance.
Key Features
-
Genuine Mercury Marine OEM 4-stroke engine oil
-
SAE 25W-40 viscosity grade
-
Advanced marine additive package for corrosion protection
-
Helps maintain viscosity under extreme heat and engine loads
-
Reduces wear and protects internal engine components
-
FC-W and FC-W Catalyst Compatible certified
Marine-specific oils outperform automotive oils in boat engines because they include enhanced rust inhibitors and shear stability additives designed for humid and saltwater environments.
Part Details
OEM Part Number: 8M0078640
Mercury Reference Number: 92-8M0078640
Product Type: 4-stroke marine engine oil
Oil Type: Synthetic blend marine oil
Viscosity: SAE 25W-40
Container Size: 4 Liters (approx. 1.06 gallons)
Compatible Mercury & MerCruiser Engines
Approved for use in all Mercury and MerCruiser 4-stroke marine engines, including:
Mercury FourStroke Outboards
-
Mercury 2.5HP β 400HP FourStroke outboards
-
Mercury Pro XS FourStroke models
-
Mercury Verado FourStroke engines
MerCruiser Sterndrives & Inboards
-
MerCruiser 3.0L
-
MerCruiser 4.3L V6
-
MerCruiser 5.0L V8
-
MerCruiser 5.7L V8
-
MerCruiser 6.2L V8
-
MerCruiser 7.4L V8
-
MerCruiser 8.2L V8
This oil is approved for outboard, sterndrive, and inboard marine engines that require 25W-40 oil.
Function
Engine oil lubricates internal components such as pistons, bearings, and camshafts while helping control temperature and reduce friction. Marine engines operate under heavier loads and constant RPM compared with automotive engines, making proper oil formulation critical.
Using Mercury marine oil helps:
-
Reduce internal engine wear
-
Prevent corrosion from moisture and saltwater exposure
-
Maintain engine cleanliness and lubrication
-
Protect engines operating at high RPM and heavy loads
Important Compatibility Note
Always confirm the recommended oil viscosity in your engine ownerβs manual. While many Mercury and MerCruiser engines use 25W-40, some newer models may specify 10W-30 or 25W-50 depending on engine design and operating conditions.
Shipping: Ships same or next day for fast Canada wide shipping. β
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3β4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us β and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity β and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.