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 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

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This is a great filter for allergies and a huge help during allergy season. It traps fine dust and pollen much better than the standard paper filters you get from the dealership, resulting in noticeably cleaner air inside the cabin. The construction feels very solid, and it fit perfectly right into the housing without any issues. If you are looking for true HEPA filtration in your vehicle, this is definitely worth the upgrade!

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Reviewed in the United States on March 13, 2026

Verified Purchase

Fort Morgan, US

★★★★★ 5

Saved over $60 and felt like a DIY hero!

Size: 7.5" x 8.7" x 1.4"

I bought the BOSCH 6092C HEPA Cabin Air Filter after a tire/service center quoted $76 to do the same job I did in no time. Instead, I watched a quick YouTube video, grabbed a screwdriver, and had it swapped out in under 5 minutes—no sweat, no special tools. The filter itself is high quality, fits perfectly, and noticeably improved the air quality in my car. No weird smells, and the airflow feels cleaner and stronger. Honestly, it’s one of the easiest upgrades I’ve ever done. If you’re even slightly handy (or just tired of paying for basic service), this is a no-brainer. Great product, easy install, and a satisfying win for anyone who likes saving money and doing things themselves.

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Reviewed in the United States on October 18, 2025