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

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.

Fitment

• 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

Specifications

Manufacturer part number

MMTC-L5P-TBV

UPC

840197710616

Shipping weight & size

1.60 lb, 8.5 × 7.5 × 2 in

Notices

• WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
• Special order item — ships direct from the manufacturer; extended lead times may apply.