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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These bags are a nice size and seem durable, especially for larger items. However, they arrived with a very strong odor that was noticeable as soon as I opened the package. I'm hoping the smell fades over time, but it was disappointing and worth mentioning. Overall, the bags are functional, but the odor keeps me from giving a higher rating.

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Reviewed in the United States on June 2, 2026

Verified Purchase

Liz A

San Leandro, US

★★★★★ 5

Exactly what I was looking for

Color: Extra Large - 3Pcs

Needed it for a shoe box gift & a couple other small clothing items & they fit perfectly. Loved that it came with some tissue paper as well. Pretty sturdy.

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Reviewed in the United States on December 27, 2025

Verified Purchase

Lorie Patton

Cuba, US

★★★★★ 5

Great quality

Color: Extra Large - 3Pcs

Great quality. I would purchase again.

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Reviewed in the United States on February 16, 2026

Verified Purchase