Exterior Components› Body Panels and Components

SIERRAMARINE

SYNTHETIC BLEND MERCRUISER STERNDRI

$65.33

SKU: S08C 18-9440-4

In Stock
In Stock
Ships by Jun 14
Free Shipping
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Description

The SIERRAMARINE 18-9440-4 is a 5-quart jug of 4-cycle engine oil. This oil is blended with premium grade synthetic and mineral-based stock, featuring superior additives specifically formulated for the stress experienced by sterndrive and inboard marine engines.

It offers advanced lubrication to reduce wear on internal engine components and eliminates thermal breakdown under high RPMs, extreme temperatures, and heavy loads. This oil is NMMA FC-W Certified and API-SL rated, ensuring outstanding performance and protection.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandSIERRAMARINE
Part NumberS08C 18-9440-4

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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