








Mishimoto
Full-Flow Transmission Thermal Bypass Valve Kit, fits Chevrolet/GMC 6.6L Duramax L5P 2017+
Full-Flow Transmission Thermal Bypass Valve Kit, fits Chevrolet/GMC 6.6L Duramax L5P 2017+
MCQUEEN
190 South McQueen Road
Suite 109
Gilbert AZ 85233
United States
Description:
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.
Key Features:
- Direct fit for 2017+ Chevrolet/GMC 6.6L Duramax L5P
- Installs in less than 1 hour
- Durable CNC-machined billet aluminum design

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