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2003-2005 6.6L LB7 / LLY Duramax Transmission Cooler Mishimoto MMTC-DMAX-03SL

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    There’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 and powerful cooling. Aside from its durable construction, this transmission cooler is significantly larger than the stock core. The Mishimoto transmission cooler boasts a 174% greater core volume, and 192% greater fin surface area than the stock 2003–2005 Duramax transmission cooler.

    The included CNC-machined adapters connect directly to the stock transmission cooler lines for leak-free cooling. Direct-fit brackets and tailor-made hoses make installation easy. Like all Mishimoto products, this transmission cooler is backed up by our Lifetime Warranty with Accident Protection for worry free cooling as long as you own it.

    Features:
    • Direct fit for all 2003–2005 Chevrolet/GMC 6.6L Duramax (LB7/LLY)
    • Stacked-plate construction for maximum durability and superior cooling
    • CNC-machined adapters make it easy to connect Mishimoto cooler to stock fluid lines or AN lines
    • 174% greater core volume than stock cooler
    • 192% greater external fin surface area over stock cooler
    • Patent #D900,161
    • Mishimoto Lifetime Warranty

    Includes:
    (1) Mishimoto Stacked Plate Transmission Cooler
    (2) CNC-Machined Quick-Disconnect to Hose Barb Adapters
    (2) Stock-style Quick-Disconnect Fittings
    (2) Transmission Hoses
    (2) Mounting Brackets
    (4) Worm Gear Clamps
    (1) Zip Tie
    Mounting Hardware

    Notes:
    This kit fits with late 2003 trucks with purple clips. Early 2003 trucks with orange clips should use MMTC-DMAX-01.
    Purchase 2003-2005 6.6L LB7 / LLY Duramax Transmission Cooler Mishimoto MMTC-DMAX-03SL

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    2003-2005 6.6L LB7 / LLY Duramax Transmission Cooler Mishimoto MMTC-DMAX-03SL

    SKU: mimMMTC-DMAX-03SL
    $498.95

    Qualifies for Free Shipping Over $199



    Fits: Duramax 2003-2005 (WITH PURPLE CLIPS)
     
    Free shipping on orders over $199**Contiguous US only
    Most in-stock orders ship in 1–2 business days
    Diesel experts: 615-962-8291
    Fits these vehicles
    • 2003 Chevrolet 6.6L LB7 Duramax
    • 2003 GMC 6.6L LB7 Duramax
    • 2004 Chevrolet 6.6L LB7 Duramax
    • 2004 GMC 6.6L LB7 Duramax
    • 2004 Chevrolet 6.6L LLY Duramax
    • 2004 GMC 6.6L LLY Duramax
    • 2005 Chevrolet 6.6L LLY Duramax
    • 2005 GMC 6.6L LLY Duramax
    Warranty: Limited Lifetime

    There’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 and powerful cooling. Aside from its durable construction, this transmission cooler is significantly larger than the stock core. The Mishimoto transmission cooler boasts a 174% greater core volume, and 192% greater fin surface area than the stock 2003–2005 Duramax transmission cooler.


    The included CNC-machined adapters connect directly to the stock transmission cooler lines for leak-free cooling. Direct-fit brackets and tailor-made hoses make installation easy. Like all Mishimoto products, this transmission cooler is backed up by our Lifetime Warranty with Accident Protection for worry free cooling as long as you own it.


    Features:
    Direct fit for all 2003–2005 Chevrolet/GMC 6.6L Duramax (LB7/[...]

    There’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 and powerful cooling. Aside from its durable construction, this transmission cooler is significantly larger than the stock core. The Mishimoto transmission cooler boasts a 174% greater core volume, and 192% greater fin surface area than the stock 2003–2005 Duramax transmission cooler.

    The included CNC-machined adapters connect directly to the stock transmission cooler lines for leak-free cooling. Direct-fit brackets and tailor-made hoses make installation easy. Like all Mishimoto products, this transmission cooler is backed up by our Lifetime Warranty with Accident Protection for worry free cooling as long as you own it.

    Features:
    • Direct fit for all 2003–2005 Chevrolet/GMC 6.6L Duramax (LB7/LLY)
    • Stacked-plate construction for maximum durability and superior cooling
    • CNC-machined adapters make it easy to connect Mishimoto cooler to stock fluid lines or AN lines
    • 174% greater core volume than stock cooler
    • 192% greater external fin surface area over stock cooler
    • Patent #D900,161
    • Mishimoto Lifetime Warranty

    Includes:
    (1) Mishimoto Stacked Plate Transmission Cooler
    (2) CNC-Machined Quick-Disconnect to Hose Barb Adapters
    (2) Stock-style Quick-Disconnect Fittings
    (2) Transmission Hoses
    (2) Mounting Brackets
    (4) Worm Gear Clamps
    (1) Zip Tie
    Mounting Hardware

    Notes:
    This kit fits with late 2003 trucks with purple clips. Early 2003 trucks with orange clips should use MMTC-DMAX-01.
    No Questions asked yet!



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    Mishimoto MMTC-DMAX-03SL Installation Instructions

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