Product images and videos 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.
Drivetrain› Automatic Transmissions and Components
COAN
9in (245MM) High Perf Race Converter
SKU: C05K COA-20425-1
Moderate — 2–4 hours
Overview
Coan Racing has extensive experience in designing and manufacturing custom automatic transmissions and components. Their engineering expertise is applied to a diverse line of performance transmissions suitable for various racing and street applications, aiming for record-setting performance.
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Part #: COA-20425-1
Torque Converter - High Performance - 9 in Diameter - 10.750 in Bolt Circle - TH350 / TH400 - Each
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
| Brand | COAN |
| Part Number | C05K COA-20425-1 |
Videos
TH400 Torque Converter Install (Made EASY)
Mountains Garage: TH350 V TH400 Strength Comparison
ATTENTION ATTENTION!!! How to space the flexplate and torque converter. SERIOUS INFORMATION!!!
The SECRET GM Transmission Part You NEVER KNEW Existed Revealed!
Jason Coan discusses TH400 transmission close ratio compound planetary sets
About MOTORMIA
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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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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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