Drivetrain Automatic Transmissions and Components

Trans Go Performance

TH400, TH475 SHIFT KIT

$30.47

SKU: T09L SK 400

In Stock
In Stock
Ships by Sep 22
Free Shipping over $200
$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The TransGo SK 400 is a valve body repair kit designed for GM 400 and 3L80 automatic transmissions. This kit fits all 400 transmissions from 1965 to the present. It is designed to correct and prevent issues such as soft, late shifts, 3rd clutch burn-up, rough 1-2 shifts, and overly sensitive passing gear.
Show original supplier description

Part #: SK 400

Components to address soft late shifts, 3rd clutch burn-up, rough 1-2, excess passing gear and late shifts.

Vehicle Symptoms
  • Soft or delayed shifts in GM 400 transmission
  • Rough 1-2 upshift on acceleration
  • Premature 3rd clutch burnout
  • Overly sensitive passing gear engagement
  • Harsh or erratic shifting under load
Relevant Conversations
  • GM 400 transmission soft shift fix
  • TransGo SK 400 installation tips
  • 3L80 shift kit vs valve body repair kit
  • Rough 1-2 shift TH400 help
  • Transmission slips and shifts late GM 400
  • P0750 code but shift solenoid ok
  • TH400 shift kit for towing
  • Valve body repair kit GM 400 symptoms
  • 3L80 premature 3rd clutch burnout fix
  • Best shift kit for GM 400 transmission

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

BrandTrans Go Performance
Part NumberT09L SK 400

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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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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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