SKU: 37194769079

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

Sale price$148.49 Regular price$164.99
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Ships within 48 hours · Estimated delivery Jul 15 - Jul 20

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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 thermal bypass valve upgrade for your 2017-2019 Chevrolet/GMC 6.6L Duramax. Our CNC-machined aluminum thermal bypass valve not only looks better than the stock unit, but it performs better too. This Mishimoto thermal bypass valve kit includes a fully serviceable thermostat for fast warm-up in cold climates. This kit also includes a thermostat bypass that can be installed to provide constant cooling in warm climates or for use in extreme driving/towing conditions. 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 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.
  • Except Preorder products are shipped in 48 hours.
  • 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: 37194769079

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lg
Massapequa, US
★★★★★ 5
Smart Design
Color: Brushed Nickel, Size: 8.85 inch
Glad I purchased these with the longer tab that hangs over the back of the cabinet door. I feel they are not likely to fall off when pulling towel off the holder. Was surprised that the foam insert did not go all the way along the inside. It is just in front and back. I didn't want the metal part scratching my cabinet door top, so I used self-stick felt pads on the inside top to prevent scratching. A quick solution to prevent possible scratching of the cabinet. Overall, a good purchase for a reasonable price. Does the job, especially when I didn't want to attach a towel rod to the wall.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 17, 2026
A
Verified Purchase
Angie Miller
Grantham, US
★★★★★ 5
These towel holders are perfect !
Color: Brushed Nickel, Size: 8.85 inch
These are awesome ! Fit very well on my kitchen cabinet doors. My cabinet doors are beveled a bit at the top so I was concerned these towel holders wouldn’t fit right but they fit great !
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Reviewed in the United States on May 31, 2026
E
Verified Purchase
Edward R.
Alexandria, US
★★★★★ 4
I would recommend
Color: Brushed Nickel, Size: 8.85 inch
Quality product, a little smaller than expected, but good.
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Reviewed in the United States on April 22, 2026
L
Verified Purchase
L. Connell
Fort Morgan, US
★★★★★ 5
Very handy ...saves paper towels
Color: Brushed Nickel, Size: 8.85 inch
Fits well under my sink doors...saves a lot of paper towels....sturdy.
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Reviewed in the United States on April 23, 2026
M
Verified Purchase
Marianne S.
Dallas, US
★★★★★ 5
good quality
Color: Brushed Nickel, Size: 8.85 inch
i have purchased similar types from other sellers and i think this is by far the best. it goes deeper into the cabinet door therefore does mot fall off and also stays in place, not moving or sliding around. . the others also have broken over time
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Reviewed in the United States on May 30, 2026

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