SKU: 95105417312

Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve Kit

Sale price$105.29 Regular price$116.99
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Ships within 48 hours · Estimated delivery Jul 26 - Jul 31

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Description

Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve KitThe Allison transmission is the backbone of your L5P Duramax. It's responsible for transmitting large quantities of torque from your V8 diesel powerplant. This torque generates a lot of heat, and if that heat isn't dissipated, it can destroy your transmission. The transmission cooler does a good job of keeping trans fluid temperatures in check, but only if the fluid can reach it. The stock cooling system of the Allison 1000 transmission utilizes an in

The Allison transmission is the backbone of your L5P Duramax. It's responsible for transmitting large quantities of torque from your V8 diesel powerplant. This torque generates a lot of heat, and if that heat isn't dissipated, it can destroy your transmission. The transmission cooler does a good job of keeping trans fluid temperatures in check, but only if the fluid can reach it. The stock cooling system of the Allison 1000 transmission utilizes an in-line thermal bypass valve that controls fluid flow to the transmission cooler. The purpose of this valve is to prevent transmission fluid from flowing to the cooler until it reaches operating temperature. The thermostat inside this valve is prone to failure, however, and when that happens, the fluid never flows to the cooler, and the transmission can overheat. That's why Mishimoto has developed a full-flow thermal bypass valve upgrade for your 2017-2019 Chevrolet/GMC 6.6L Duramax. Our CNC-machined aluminum full-flow thermal bypass valve not only looks better than the stock unit, but it performs better too. This Mishimoto thermal bypass valve eliminates the internal thermostat, providing full fluid flow to the transmission cooler in all running conditions. This setup is ideal for owners in warm climates, those performing heavy towing, and trucks needing the best possible cooling efficiency for their transmission. The Mishimoto thermal bypass valve features strategically machined internal passages, providing improved flow over the stock valve for more effective cooling. In addition, cooling fins machined into the valve body adds even more heat dissipation. This 2017-2019 Chevrolet/GMC 6.6L Duramax L5P Full-Flow Thermal Bypass Valve Kit is built to last a lifetime with a durable black anodized finish and our Mishimoto Lifetime Warranty.

This Part Fits:

Year Make Model Submodel
2017-2019 Chevrolet Silverado 2500 HD High Country
2017-2019 Chevrolet Silverado 2500 HD LT
2017-2019 Chevrolet Silverado 2500 HD LTZ
2017-2019 Chevrolet Silverado 2500 HD WT
2017-2019 Chevrolet Silverado 3500 HD High Country
2017-2019 Chevrolet Silverado 3500 HD LT
2017-2019 Chevrolet Silverado 3500 HD LTZ
2017-2019 Chevrolet Silverado 3500 HD WT
2017-2019 GMC Sierra 2500 HD Base
2017-2019 GMC Sierra 2500 HD Denali
2017-2019 GMC Sierra 2500 HD SLE
2017-2019 GMC Sierra 2500 HD SLT
2017-2019 GMC Sierra 3500 HD Base
2017-2019 GMC Sierra 3500 HD Denali
2017-2019 GMC Sierra 3500 HD SLE
2017-2019 GMC Sierra 3500 HD SLT
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
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  • Delivery to the USA:
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Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
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SKU: 95105417312

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NM_HS
Pawtucket, US
★★★★★ 5
Hands free comfort!!
Size: 5 Big Kid, Color: Black
Superb comfortable, great quality and got it at such a good price. My daughter is very happy and wears these every day since a couple of months and they still look new. Best part hands free!!
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Reviewed in the United States on December 1, 2025
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omri
West Palm Beach, US
★★★★★ 5
good shoes
Size: 8 Toddler, Color: Black, Size: 8 Toddler, Color: Black
fit great the child like it
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Reviewed in the United States on May 21, 2026
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Carly Perez
Waukegan, US
★★★★★ 5
Toddler approved
Size: 8 Toddler, Color: Black
My kid loves these shoes. We’ve bought them multiple times. She can get them on and off easily and they stand up to her wild adventures.
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Reviewed in the United States on May 3, 2026
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Allyssa
Carnegie, US
★★★★★ 5
So cute and so worth it!
Size: 3 Little Kid, Color: Turquoise
AMAZING for my 7 year old daughter. She can tie shoes but I no longer have to wait on her to do so. It takes 2 seconds for her to put these on and she says that they are super comfortable. We have been to Silver dollar City multiple times and she never complains about her feet hurting! They are easily washed in the washer. They hold up great. I think they are very much worth the money! Fit normal.
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Reviewed in the United States on December 8, 2025
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Morgan
San Leandro, US
★★★★★ 4
Our everyday shoe!
Size: 13 Little Kid, Color: Turquoise
Great shoes and good fit. Fits as expected. The sole has worn down a bit quicker than I had hoped but my kiddo wears them everyday. I would buy them again for sure!
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Reviewed in the United States on November 30, 2025

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