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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Been using these for months, great quality. No issues what so ever. I compared price to the 2 main big box stores and this is the best for your bucks. You get a lot more and they are of the same quality. I used to get mine from a big box store with military discount of 10% and this is still a better deal. They fit exactly like the filter I took out, so size is the same. I live FL and run my AC constantly. These last about 2-3 months each. They do no lose their rigidity. They are built with very high quality material. They catch a lot of dust, you can see how dirty they are when replaced. PROS - great quality and last 2-3 months in my AC running constantly - you get a lot for your money when compared to the big box stores - catch a lot of dirt, filters are really dirty after use - very rigid which makes it easy to installation - reinforced wire mesh CONS - None

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Reviewed in the United States on May 31, 2026

Verified Purchase

Arlo

West Palm Beach, US

★★★★★ 5

Top quality filters at a good price.

Style: 20x30x1

These filters are good quality. They are reinforced and hold their shape. They fit perfectly in my filter holder. The thing I like is that the filters were bundled together and shipped in a sturdy box. Other filters I have ordered showed up in a flimsy box and were damaged.

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Reviewed in the United States on May 22, 2026

Verified Purchase

La Quinta

Whiting, US

★★★★★ 5

Excellent to have on hand

Style: 16x25x1

Excellent, time-saving purchase. Sturdy, easy to install.

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Reviewed in the United States on May 27, 2026