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

Thoroughbred Sku #: WCF100469

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$57.23

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(859) 737-4966

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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

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.

The WCFab Transmission Cooler Thermostat Bypass Plug is a quick and easy install and will work with the following range of GM vehicles equipped with a factory installed transmission cooler thermostat bypass:

  • 2017-2019 Chevrolet Silverado & GMC Sierra 2500HD/3500HD with 6.6L Duramax Diesel
  • 2014-2018 Chevrolet Silverado & GMC Sierra 1500 with 4.3L 6 Cyl, 5.3L 8 Cyl, and 6.2L 8 Cyl Gas Engines
  • 2015-2020 Chevrolet Suburban, Tahoe & GMC Yukon with 5.3L 8 Cyl, and 6.2L 8 Cyl Gas Engines
  • 2015 Cadillac Escalade with 6.2L 8 Cyl Gas Engine

Note:

  • Anything powder coated will have a lead time of 15-25 days.
  • Non powder coated products will have a 2-3 day lead time.

WC Fab Transmission Cooler Thermostat Bypass Plug 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
  • For more information on WC Fab call us at 1-859-737-4966.

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  • 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.