SKU: 93206138931

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

Sale price$80.95 Regular price$89.95
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Ships within 48 hours · Estimated delivery Aug 23 - Aug 28

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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
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Exchange/Return Notes
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  • 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: 93206138931

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4.1 ★★★★★
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Cali Mom
Lake Worth, US
★★★★★ 5
Perfect size, high quality
Size: 7.7" x 7.7" x 1.7", Color: Black (Metal Silvered)
I had a previous catch all tray that I bought on amazon, it used buttons on the 4 corners to turn a flat cardboard into a tray. Over time, the catch all tray got filled up, not just with a wallet, keys and eyeglasses but eventually business cards and other knick knacks. With all the items inside the tray, sometimes the buttons would start to pop out. It wasn't awful, more of an annoyance. But it was time for me to find a more durable tray. I looked on amazon and added 6 different trays that had "potential" into my shopping cart. Then I carefully evaluated each one and deleted them out of my cart until there was only one left. Some had multiple compartments. Some were larger than this one. I felt the ones with compartments would limit my ability to put the things I want in there. Also, I didn't want it so big that it took up too much desk space. Ultimately, I felt this was the perfect size. I'm extremely happy with it, the quality is really nice and it looks and feels durable. No more loose buttons and spilled knick knacks.
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Reviewed in the United States on October 14, 2024
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Verified Purchase
Denise
Draper, US
★★★★★ 5
Keeps clutter away
Size: 7.7" x 7.7" x 1.7", Color: Black (Metal Silvered)
This works great to corral all my notes I write on post its or small notes. Keeping them hidden from the desk top b/c or the depth but still visible to me. Much better than keeping on the plotter. Looks great in quality .
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Reviewed in the United States on October 25, 2025
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MovieGuy
Omaha, US
★★★★★ 5
Attractive, Simple, And Well-Made
Size: 7.7" x 7.7" x 1.7", Color: Orange (Metal Glided)
I use this as a "catchall". A place to stash things like my wallet and keys when I enter the door, so that I don't use them (I had been prone to that!). It serves it's purpose well. It's both sturdy and attractive, and a good size for a "catchall". Recommended for those like me who need such things.
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Reviewed in the United States on April 8, 2024
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Kirstin Gramith
West Palm Beach, US
★★★★★ 4
Good quality, orange color
Size: 7.7" x 7.7" x 1.7", Color: Orange (Metal Glided), Size: 7.7" x 7.7" x 1.7", Color: Orange (Metal Glided)
The quality is surprisingly good but the color is much more orange toned in person.
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Reviewed in the United States on April 17, 2024
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kenneth
Chelsea, US
★★★★★ 5
Holder
Size: 7.7" x 7.7" x 1.7", Color: Black (Metal Silvered)
It’s great for my keys and wallet and other stuff I use it every day
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Reviewed in the United States on August 30, 2025

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