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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I never write reviews but these are AWESOME! I have had low iron for about 10 years and nothing I’ve tried in the past (changing my diet, other multi-vitamins, prescribed iron supplements, etc.) has ever gotten rid of the fatigue that comes with it. I started taking these about a month ago and I feel like a brand new person! I can get through the day without taking a nap or multiple, which has bettered not only my sleep schedule but my productivity all around! I could not recommend enough. They do have a nasty smell but I just breathe through my mouth until I’ve swallowed it lol. The smell is 100% worth the outcome in my opinion.

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Reviewed in the United States on September 16, 2025

Verified Purchase

McMe

West Palm Beach, US

★★★★★ 5

Ordered multiple times and am pleased!

I got these when one a day stopped making the gelcap minis that I loved and used for years. I prefer gelcaps over tablets for better absorption, and these don't disappoint at all. They're good quality, as I notice the difference when I don't take them. They're easy to swallow despite being a somewhat larger capsule, and very comparable in contents and values to the ones I took before. I feel better when I take them, and that's enough for me. Shipping was fast and they arrived undamaged, every time I've ordered them.

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Reviewed in the United States on July 30, 2025