Mercury Synthetic Blend Engine Oil 10W-30 8M0149203
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Mercury 8M0149203 is a genuine Mercury Marine SAE 10W-30 synthetic blend 4-stroke marine engine oil. Retail and dealer listings identify this part number as a 1 quart bottle, intended for marine 4-stroke applications where 10W-30 is specified.
Key Features
This oil is a 10W-30 synthetic blend formulated for marine use, with corrosion protection, shear strength, and viscosity retention designed for high-rpm, high-load operation. Mercury says it is engineered for 4-stroke marine engines and exceeds marine engine manufacturer warranty requirements and recommendations.
Engine Compatibility
Mercury’s current 10W-30 synthetic blend guidance covers all 4-stroke outboards up to 150 HP, plus 3.4L V6 and 4.6L V8 outboards where 10W-30 is called for. Always confirm the required oil grade in the owner’s or service manual for the exact engine model and serial number.
Serial Number Fitment Notice
Please confirm the correct oil specification using your exact Mercury or MerCruiser model and serial number before purchase. Mercury’s official Parts Catalog is the safest way to verify application details.
When This Part Needs Replacement
Use this oil during routine oil changes on applicable 4-stroke marine engines. Fresh marine-grade oil is important for wear protection, corrosion resistance, and keeping the engine protected during both operation and storage. This usage is supported by Mercury’s product guidance for 10W-30 marine oil.
Installation Notes
Use only the oil viscosity specified for the engine. This product is intended for marine 4-stroke use, and Mercury advises checking the owner’s manual or service manual for the correct application and service instructions.
Alternate / Superseded Part Numbers
No confirmed superseded part number was established from the sources reviewed. The exact catalog number consistently shown is 8M0149203.
Parts Desk Insight
Marine engine oil is not just about viscosity. The corrosion inhibitors and load-handling additives matter, especially on engines that spend time in humid, salty, or seasonal storage conditions. Matching the exact Mercury-recommended oil grade is one of the easiest ways to protect long-term engine life.
Shipping: Ships same or next day for fast Canada wide shipping. ⚓
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 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 — 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 — 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.