Drivetrain› Automatic Transmissions and Components

Transmission Specialties, Inc

GM TH400 Planetary Gear Set 2.10-1.40 Ratio

$1,768.29

SKU: T01H 400-600

In Stock
In Stock
Ships by Aug 31
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$100 Minimum Order
Non-Returnable Item
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Overview

The Transmission Specialties 400-600 is a straight-cut billet gear set designed for the TH400 automatic transmission. It features a 2.10:1 first gear ratio, which softens the initial hit to the tires for improved traction and better elapsed times. The set also includes a 1.40:1 second gear and a 1:1 third gear. Constructed from 8620 steel forged components, it is rated for up to 2000 horsepower and comes fully assembled with high-performance bushings and Torrington bearings.
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GM TH400 Planetary Gear Set 2.10-1.40 Ratio

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.

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Specifications

BrandTransmission Specialties, Inc
Part NumberT01H 400-600

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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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