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

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

SKU:MISMMTC-L5P-TBV

Category: Transmission Coolers
Vendor: Mishimoto
You save 20% ($31.86)
Regular price $128.95
Regular price $160.81 Sale price $128.95
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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+ 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 add even more heat dissipation. This 2017+ 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.

This Part Fits:

Year Make Model Submodel
2021 Chevrolet Silverado 2500 HD Custom
2017-2021 Chevrolet Silverado 2500 HD High Country
2017-2021 Chevrolet Silverado 2500 HD LT
2017-2021 Chevrolet Silverado 2500 HD LTZ
2017-2021 Chevrolet Silverado 2500 HD WT
2017-2021 Chevrolet Silverado 3500 HD High Country
2017-2021 Chevrolet Silverado 3500 HD LT
2017-2021 Chevrolet Silverado 3500 HD LTZ
2017-2021 Chevrolet Silverado 3500 HD WT
2020-2021 GMC Sierra 2500 HD AT4
2017-2021 GMC Sierra 2500 HD Base
2017-2021 GMC Sierra 2500 HD Denali
2017-2021 GMC Sierra 2500 HD SLE
2017-2021 GMC Sierra 2500 HD SLT
2020-2021 GMC Sierra 3500 HD AT4
2017-2021 GMC Sierra 3500 HD Base
2017-2021 GMC Sierra 3500 HD Denali
2017-2021 GMC Sierra 3500 HD SLE
2017-2021 GMC Sierra 3500 HD SLT

Shipping & Delivery

We can ship to virtually any address in the world. Note that there are restrictions on some products, and some products cannot be shipped to international destinations. For international orders, please Contact Us. If you select US shipping rates and are shipping internationally, please be advised you will be contacted to compensate the difference in shipping fees.

Processing takes about 3 to 5 business days before your order ships. We do not process or ship orders on weekends. If you order an item that's on backorder, we will reach out with an estimated arrival time. If you have any questions about shipping make sure to email us at sales@onlinetsm.com or call our reps today at 732-638-5268.

If by any chance, your package that has been delivered by the carrier is lost/stolen, YOU (THE BUYER) are responsible for working with the carrier and us, Tri-State Motorsports to recover your package. You must contact us and the shipping company within 48 hours of delivery for lost/damage claims. You are covered by the basic insurance amount APPROVED by the shipping center. We DO NOT refund or reship product for claims that are denied by the shipping company.

FAQs

When will my product ship out?

Processing takes about 3 to 5 days before your order ships. Some orders may take longer than usual to process and ship. If you order an item that's on backorder, we will reach out with an estimated arrival time. Refunds are subject to a 20% restocking fee. Cancellations are subject to 10% cancellation/processing fee under no exceptions.

What's the Warranty on our products?

Unless the product is manufactured by Tri-State Motorsports or TSM Race, ALL Warranties go through the Manufacturer directly. Please visit their official website and get in contact with them in regards to your warranty. We will supply you with any invoice or tracking information the manufacturer asks you for.

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One of our major promotions is the TSM Bucks Loyalty Program. You will earn 1 TSM point for every dollar you spend with us. These points can be redeemed for rewards when you reach certain thresholds. 

TSM Bucks Info

If you subscribe to marketing emails, you will be given a discount code for 5% off your order that you can use at any time. Our Instagram page also has a variety of weekly promotions in our stories and posts. Some restrictions may apply depending on MAP policies.

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