SKU: 25597115635

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

Sale price$89.95 Regular price$99.95
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USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Jul 25 - Jul 30

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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+ 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 add even more heat dissipation. This 2017+ 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.
Shipping Notes
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Exchange/Return Notes
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SKU: 25597115635

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𝐿𝒾𝓋𝒾𝓃𝑔 𝓉𝒽𝑒 𝒹𝓇𝑒𝒶𝓂!
Alexandria, US
★★★★★ 4
Clean, easy drinking water with a mild taste
Size: 16.9 Fl Oz (Pack of 15)
This bottled water has a clean and mild flavor that makes it easy to drink throughout the day. It is light and refreshing without any strong mineral aftertaste, which keeps it simple and consistent. The bottles are convenient for carrying around, and the 15 pack is practical for keeping stocked at home, work, or in the fridge. They are easy to open and store without taking up too much space. I like that the taste is consistent across bottles and works well for everyday hydration without any added flavor or heaviness. One thing to keep in mind is that it is a very basic bottled water option, so it stands out more for convenience and consistency rather than anything unique. Overall, this is a reliable everyday water choice that is simple, clean tasting, and easy to keep on hand.
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Reviewed in the United States on May 20, 2026
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Kevin
New York, US
★★★★★ 5
Cheap and delicious water.
Size: 16.9 Fl Oz (Pack of 12)
Delicious! I can't stand some bottled water like Dasani, but once I got it ice cold, it's really nice. Bottles arrived in perfect condition with no leaking.
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Reviewed in the United States on May 19, 2026
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Jo
Massapequa, US
★★★★★ 5
Pure Water
Size: 16.9 Fl Oz (Pack of 12)
Good value for the money. I’m Waiting for water to go back on special. I def will buy again
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Reviewed in the United States on May 22, 2026
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Maria Swanenburg
Dallas, US
★★★★★ 5
Economical, great taste and refreshing.
Flavor Name: Kiwi Strawberry, Size: 16.9 Fl Oz (Pack of 12)
very refreshing and nice flavor. I will definitely buy again. Great bottle size for hiking. Ingredients are blended well and the calorie count is low. Buying a multi-pack is also economical.
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Reviewed in the United States on May 21, 2026
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SimplyBoldMomEdit
Grantham, US
★★★★★ 5
Crisp, Refreshing, and a Family Favorite
Flavor Name: Kiwi Strawberry, Size: 16.9 Fl Oz (Pack of 12)
Propel Kiwi Strawberry is one of our favorites. It’s crisp, refreshing, and has just the right amount of flavor without being overpowering. The kiwi strawberry taste is especially enjoyable and makes it easy to drink throughout the day. We also like that it’s zero calorie and includes electrolytes and vitamins, making it a great option for staying hydrated during workouts or busy days. Overall, a consistently refreshing drink that we always keep stocked in the house.
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Reviewed in the United States on April 24, 2026

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