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
B&M
TRANSKIT 65-87 TH400
SKU: B00M 20229
Moderate — 2–4 hours
Overview
Show original supplier description
Part #: 20229
A B&M transmission in a box! Transform your automatic transmission into a full-tilt B&M performer! This is our ultimate transmission kit - it comes complete with full instructions on how to assemble your transmission to B&M specifications.
Features:
- Replacement Valves
- Modification Components
- Complete Overhaul Gasket Set
- High Performance Friction Materials
Transmission Rebuild Kit - Automatic - Transkit - Clutches / Bands / Filter / Gaskets / Seals - TH400 / TH375 / M40 - Kit
Vehicle Symptoms
- Sluggish automatic transmission shifts
- Delayed engagement when shifting into gear
- Transmission slips between gears under load
- Harsh or erratic shifting at low speeds
- Lack of engine braking on downhill grades
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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
Fitment Guaranteed
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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
| Brand | B&M |
| Part Number | B00M 20229 |
About MOTORMIA
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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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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.
Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.
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