Mishimoto 03-05 Chevrolet / GMC 6.6L Duramax (LB7/LLY) Transmission Cooler

Mishimoto 03-05 Chevrolet / GMC 6.6L Duramax (LB7/LLY) Transmission Cooler

Marsoni

M251S

$249.47

Get it in 3 business days with 1 day shipping. Friday, May 29

Mishimoto 03-05 Chevrolet / GMC 6.6L Duramax (LB7/LLY) Transmission CoolerThere's no greater enemy for a transmission than heat. Whether your 2003 2005 Chevy GMC 6. 6L Duramax is a dedicated tow vehicle, hardworking fleet truck, or a daily driver with a liking for the drag strip, you need to ensure that your transmission runs cool. Luckily, Mishimoto has developed a direct fit transmission cooler to do just that. Our 2003 2005 Chevy GMC 6. 6L Duramax transmission cooler utilizes a stacked plate design for maximum durability

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Your Mishimoto 03-05 Chevrolet / GMC 6.6L Duramax (LB7/LLY) Transmission Cooler orders ship within 1-2 business days.

Delivery Options:

Standard: 3-7 business days
Fast: 2-3 business days
Express: 1-2 business days

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You'll receive a tracking link by email once your Mishimoto 03-05 Chevrolet / GMC 6.6L Duramax (LB7/LLY) Transmission Cooler ships.

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Exchange/Return Notes

We offer a 30-day return/exchange service after receiving.
Final sale items are not eligible for returns or exchanges.
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This product was definitely different than the original I have a 2001 Bayliner with a 3.0 MerCruiser and an alpha one second GEN drive The kit worked but the bottom gasket had a weird cut different than the original I added a gasket maker just in case (Yamaha Lube) Brand! All in all kit was fine, One thing to note is the directions that come with the kit at least for my version we’re not for the same alpha one second GEN 4 stroke kit that I got they were for a two-stroke in the pictures didn’t look the same as the parts that I had got which is fine but it’s miss leading when you send a 4 stroke kit but 2 stroke 90hp to 200hp alpha one directions! If it craps out this review will change

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Reviewed in the United States on June 30, 2020

Verified Purchase

Air Assault

Phoenix, US

★★★★★ 5

Super great product. Has the power and functionality to get you repairing fast!

Super great product. Has the power and functionality to get you repairing fast! Fully recommend this and it has worked great since I've owned it. Still going strong in the durability and design looks like it will keep it going strong for many years. Highly highly recommend buying this. Will work in Kuwait, Iraq, UAE, and Saudi. Good for Camps around the CENTCOM area!

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Reviewed in the United States on October 6, 2025

Verified Purchase

Jed V

San Leandro, US

★★★★★ 5

Solid Product

worked well, easy to install.

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Reviewed in the United States on November 3, 2025