SKU: 37194769079

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

Sale price$148.49 Regular price$164.99
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Ships within 48 hours · Estimated delivery Jul 24 - Jul 29

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For Your Every Summer RSVP, with Code: SUMMER15

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 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.

This Part Fits:

Year Make Model Submodel
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
Shipping Notes
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  • Delivery to the USA:
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Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
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SKU: 37194769079

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4.5 ★★★★★
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lyn
Massapequa, US
★★★★★ 5
Great for oily skin!
Size: 3 Fl Oz (Pack of 1)
Definitely leaves white cast, I’m pretty fair skinned, makes me look like a ghost. Just rub it in your hands first, breaks into the mineral so minimize the white cast look. It feels lightweight and as someone with pretty oily skin it does a pretty good job!
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Reviewed in the United States on April 30, 2026
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Nathan
Lowell, US
★★★★★ 4
Great for Oily, Rash-Prone Skin, But Be Wary of the Residue
Size: 1.7 Fl Oz (Pack of 1)
This sunscreen is a really solid option if you have sensitive, rash-prone, and oily skin like mine. I’ve found it’s one of the few sunscreens that doesn't cause any irritation, which is a huge benefit for me. On top of that, it leaves a truly matte finish, so I don't feel greasy or shiny throughout the day. The only reason I can't give it five stars is that it leaves behind small, dried white bits on my face. They can be a bit annoying and make the application look a little messy. Overall, it's a good sunscreen that works well with my skin type, but the white residue is a definite drawback.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on August 24, 2025
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Verified Purchase
Brent Freeman
Los Angeles, US
★★★★★ 5
This stuff is magic!
Size: 1.7 Fl Oz (Pack of 1)
I farm and garden. I spend hours outdoors in the summer, and for years, I’ve hated wearing sunscreen because it made my face feel hot and sticky. This sunscreen is none of that. I received a small sample tube of it from the dermatologist and instantly fell in love with it. It goes on smooth and covers well. But the thing I love about it is that I don’t feel like I’m wearing sunscreen once it absorbs into my skin. I forget about it! It doesn’t combine with my sweat and run into my eyes, making them sting. It doesn’t irritate sensitive skin or clog my pores. This stuff is magic and I will be using it daily. It’s not the least expensive sunscreen out there, but it’s worth it!
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Reviewed in the United States on May 12, 2026
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Jennifer
Birmingham, US
★★★★★ 5
Highly Recommend.
Size: 1.7 Fl Oz (Pack of 1), Size: 1.7 Fl Oz (Pack of 1)
Excellent sun protection with a lightweight, non-greasy formula. It feels great on the skin and has become a staple in my daily routine. Will buy again!
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Reviewed in the United States on May 26, 2026
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May
Grantham, US
★★★★★ 3
Terrible white cast
Size: 1.7 Fl Oz (Pack of 1)
You will look like you just got blasted by Jack Frost in the middle of the summer. This sunscreen could double as a hair identifier from the way it clings to each strand, leaving an incredibly noticeable white residue. I am very fair and on my skin itself the white cast is much less obvious/fades, my eyebrows on the other hand? Frostbitten. Snow swept. Bringing to mind polar bears and penguins. It's an alright sunscreen. Does the job. Does not look good while doing it.
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Reviewed in the United States on March 18, 2026

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