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

$154.24

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 waist bag is super practical and lightweight, perfect for days when I don’t want to carry a full purse. The fabric feels sturdy and the zipper works smoothly, nothing cheap or flimsy. It actually fits more than it looks phone, keys, lip balm, small wallet all organized without feeling bulky. The strap adjusts well and stays in place, and it’s comfortable to wear crossbody or around the waist. It’s definitely more for essentials than for carrying a lot, but for quick errands, walks, gym or travel it’s perfect. Clean design, good quality, and easy to match with any outfit.

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Reviewed in the United States on December 7, 2025

Verified Purchase

NDPEGARS

Whiting, US

★★★★★ 5

Great Bag

Size: One Size Fits Most, Color: (025) Castlerock / Black / Black

Plenty of space even for my book on the plane. No more need for a personal item. I will say that I made the mistake of hanging my hands on the belt bag and tweaked the muscles in my neck from that. Great durable back though. I paid around $20-25

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Reviewed in the United States on July 21, 2025

Verified Purchase

Alicia Ewan

Grantham, US

★★★★★ 5

Lots of room

Size: One Size Fits Most, Color: (001) Black / / White

This bag has more room than you would think, for something smaller.

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Reviewed in the United States on May 4, 2026