Drivetrain› Manual Transmissions and Components

Synchrotech

MK-SYN125 Carbon Master Kit

$808.45

SKU: SYN-MK-SYN125

In Stock
In Stock
Ships by Sep 13
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$100 Minimum Order
30 Days Return
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Overview

The Synchrotech MK-SYN125 is a carbon master kit for L15B 6-speed transmissions. This kit is designed for the 2016-2020 Honda Civic Si and EX-T Turbo models.
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The Synchrotech MK-SYN125 Carbon Master Kit is a comprehensive rebuild solution for the 6-speed manual transmission found in specific Honda Civic models. This kit is engineered to strengthen and rebuild the transmission, offering enhanced durability and performance for the L15B engine. Designed as a direct fit for the 2016-2020 Honda Civic Si and EX-T Turbo variants equipped with the 6-speed transmission, this master kit includes all necessary components for a thorough rebuild. The use of carbon composite lining in the synchronizers, developed using technology from the aerospace industry, aims to provide improved shifting feel and longevity. This master kit is specifically intended for the 10th generation Honda Civic with the L15B engine and 6-speed manual transmission, including both Si and EX-T Turbo trims from model years 2016 through 2020.

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

BrandSynchrotech
Part NumberSYN-MK-SYN125
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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