Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve Kit
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Regular price
$163.00
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This product is selected for proper fitment and compatibility with the listed engine application. Our team is available to assist with fitment questions, installation considerations, and supporting components to ensure a smooth install and reliable performance.
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Compliance & Restrictions
California Proposition 65 (Prop 65)
WARNING: This product can expose you to chemicals which is known to the State of California to cause cancer and/or reproductive harm.
For more information, visit www.P65Warnings.ca.gov.
CARB / California Emissions Compliance
This item may be restricted in California and other regions with emissions regulations. If applicable, it is intended for
competition/off-road use only unless otherwise stated. It is the customer’s responsibility to confirm local compliance before purchase.
Orders shipping to restricted areas may be canceled.
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.
Shipping Height: 2.0
Shipping Length: 8.5
Shipping Width: 7.5