Drivetrain› Automatic Transmissions and Components

G.S.I.SPORTS

12 FL. OZ. CUP- DELUXE

$20.84

SKU: G03C 8308

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In Stock
Ships by Jun 19
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Description

The Sierra 18-8308 is a shift shaft seal designed for marine applications. It features specific dimensions including an outer diameter of 0.625 inches, a shaft size of 0.297 inches, and a width of 0.156 inches. This seal is interchangeable with Mercury Marine part number 26-30696.

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

BrandG.S.I.SPORTS
Part NumberG03C 8308

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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