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

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

Marsoni

M251S

$99.95

Get it in 3 business days with 1 day shipping. Friday, May 29

Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve KitSKU: MMTC L5P TBVFF UPC: 840197710609 Mishimoto 2017+ GMC 6. 6L Duramax L5P Transmission Thermal Bypass Valve Kit Upgrade your 2017 2021 Chevrolet Silverado 2500 HD 3500 HD and GMC Sierra 2500 HD 3500 HD with L5P 6. 6L Duramax using the Mishimoto full flow thermal bypass valve kit. This direct fit replacement eliminates the stock thermostat that fails and blocks fluid flow to the cooler causing overheating. Experience constant transmission cooling for

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We offer a 30-day return/exchange service after receiving.
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I'm not a man, but I'm a nonbinary person with a big bottom and have tried many quality boxer brands over the years (including the unisex brands). These are my absolute favorite brand of boxers. They're super comfortable. It's taking me a while because I just keep forgetting to stock up but they are replacing all of my other boxers.

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Reviewed in the United States on March 8, 2026

Verified Purchase

Sara meow

Battle Creek, US

★★★★★ 3

Too large

Size: Medium, Color: Burgundy,lake Blue,dazzling Blue,bijou Blue

Nice but medium size was just too large. Suggest ordering one size smaller.

WAS THIS REVIEW HELPFUL?YesReportShare

Reviewed in the United States on February 20, 2026