SKU: 3942758100

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

Sale price$133.16 Regular price$147.95
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USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Jul 20 - Jul 25

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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+ 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.
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • 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]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 3942758100

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4.1 ★★★★★
Based on 23 reviews
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Verified Purchase
Mary Freeman
Waukegan, US
★★★★★ 5
amazing
Color: Large Set of 4
good buy worked well
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 13, 2026
S
Verified Purchase
Steve
Natrona Heights, US
★★★★★ 4
3.5, Not 3.0
Color: Medium Set of 6
These balls were almost exactly what I needed. I was replacing my boy’s favorite ball, which is the 3” squeaky, spikey ball that fits in the chuck it launcher. Unfortunately I saw the shiny object next to it and because there were SIX balls and a dollar less, I failed to see that these are 3.5” balls instead of 3”…. Great balls but no fitty in the slingy. Buyer beware. No chuck it no problem. Save a buck.
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Reviewed in the United States on March 9, 2026
H
Verified Purchase
HollisHoHo
Lake Worth, US
★★★★★ 5
MY CHIHUAHUA LOVES THESE BALLS!!
Color: Samll Set of 8
My little chihuahua, BamBam, is addicted to balls, especially little balls that squeak! However, any balls that have material on them, BamBam will tear them apart, swallow the material and then get an upset tummy! These balls saved the day! BamBam LOVES them & she cannot tear them apart! They hold up so well! No matter how much BamBam plays with them, they keep squeaking away!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on July 15, 2025
L
Verified Purchase
Laurens springerslng
Omaha, US
★★★★★ 5
Great thick squeaky ball
Color: Large Set of 2
These are good thick rubbery squeaky balls. My boy loves them! He's 75lbs. Strong chewer. I hav hard time squeezing to squeak, but he doesn't... He loves it!!!
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Reviewed in the United States on March 24, 2026
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Verified Purchase
g a ross
Lake Worth, US
★★★★★ 5
Squeaky ball
Color: Large Set of 4
Perfect squeaky ball. Dogs love them. I love that they're durable and their thickness aids their durability. My Great Dane will play alone for hours with a ball.
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Reviewed in the United States on June 20, 2025

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