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WCFab Transmission Cooler Thermostat Bypass Plug - 17-19 Duramax L5P

Thoroughbred Sku #: WCF100469

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$59.17

NOTE: These products are made to order and can experience extended lead times.

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Product Details

Product Name: WC Fab Transmission Cooler Thermostat Bypass Plug - 2017-2019 GM Duramax L5P
Manufacturer: WC Fab
Manufacturer Part #: WCF100469
Thoroughbred Diesel Part #: WCF100469
Fitment Notes: 2017-2019 GM Duramax L5P

2017-2019 L5P Duramax Billet Anodized Transmission Cooler Thermostat Bypass Plug, The stock thermostatic bypass for warming up the Allison quickly in cold weather conditions is a good idea in principle, but in practice we've seen the valve fail forcing trans fluid around the cooler in warm weather conditions that cause dangerous fluid temperatures for built and stock transmissions alike. We've been running this design on our shop development trucks and with our built transmissions successfully and are now making them available for purchase separately due to popular demand. Recommended for trucks with stock or built transmissions and performing heavy towing in warm climates to help keep fluid temperatures in check.

Note (Current WC Fab Lead Times):

  • In Stock Items: 7-10 Business Days
  • Most Built to Order Powder Coated Items: 10-15 Business Days
  • Traction Bars: 10-15 Business Days

Features:

  • CNC Machined Billet Aluminum Thermostatic Bypass Plug
  • Black Anodized Finish
  • High temperature silicone O-ring seals
  • Reduces fluid flow restriction to trans cooler
  • Simple Installation
  • Experience fluid temperature drops from 15-50 degrees F
  • Direct replacement of the failure prone OEM thermostat
  • Easy swap back to OEM setup for cold weather use

Reviews

  • I have chevy 2022 3500 HD duramax in 10 speed I think does WCFab Transmission Cooler Thermostat Bypass Plug - 17-19 Duramax L5P work for that year and transmission. Does this void the powertrain warranty?

    Kevin Myers | 4/22/2023

    17-19 Duramax L5P. you would need to check with your service provider about warranty.

  • Wil this work on a 2020 silverado 5.3 8 speed transmission?

    Josh | 4/14/2021

    No, designed for the Allison transmission.