Drivetrain› Automatic Transmissions and Components

SIERRAMARINE

OVERHAUL KIT

$471.59

SKU: S08C 18-2591

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Description

The Sierra 18-2591 is a comprehensive overhaul kit designed specifically for Borg-Warner Velvet Drive 71 and 72 series marine transmissions. This complete service kit contains all the essential gaskets, seals, and O-rings needed for a thorough transmission rebuild, addressing common issues like fluid leaks, sluggish shifts, and corrosion from saltwater exposure and high torque loads.

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 18-2591

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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