Drivetrain› Manual Transmissions and Components

MFactory

4.05 Final Drive Gear Set, B18C Series

$787.95

SKU: MF-TRS-02B4A

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
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Professional / shop required

Overview

The MFactory Final Drive Gear Set is a replacement drivetrain component designed for Honda B18C/C1/C5 series engines. This 4.05 ratio gear set is intended for use in hydraulic transmissions featuring a 116.8mm ring gear hole.
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The MFactory Final Drive Gear Set serves as a direct-fit replacement for Honda B18C/C1/C5 engines, specifically engineered for B-series hydraulic transmissions equipped with the larger 116.8mm ring gear hole diameter. This set provides a 4.05 final drive ratio, allowing for refined gear performance in compatible applications, including the 1994-2001 Acura Integra GS-R and 1996-2001 Integra Type R. Compatibility is strictly limited to hydraulic transmissions utilizing the specified 116.8mm ring gear hole. This component is not compatible with earlier cable-actuated B-series transmissions or units equipped with the smaller 109mm diameter ring gear hole. Users should verify their specific transmission configuration before installation, as incorrect ring gear hole sizing will prevent proper fitment.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandMFactory
Part NumberMF-TRS-02B4A
CategoryDrivetrain
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Returns & Fitment

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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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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