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Mishimoto 2020+ Chevrolet / GMC Duramax L5P 6.6L Transmission Cooler

Mishimoto 2020+ Chevrolet / GMC Duramax L5P 6.6L Transmission Cooler



Regular price $350.95
Sale price $350.95 Regular price $386.00

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The factory transmission cooling on the 2020+ Chevrolet and GMC Duramax L5P 6.6L is sized for stock duty, and fluid temperatures climb fast under the sustained load of towing and heavy hauling. Heat is what wears a transmission out. The Mishimoto Transmission Cooler attacks the problem with raw capacity: a tube-and-fin core with a 245% increase in core volume over stock, giving the system far more headroom to keep fluid temperatures in a safe range when the truck is working hardest.----The core also adds a 137% increase in frontal area, putting more of the cooler directly in the incoming airstream, and a 173% increase in external fin area to move heat from the fluid into the air more efficiently. All-aluminum construction handles the thermal demands of stock and modified Duramax trucks alike, and the cooler retains the factory transmission line connections for a clean, complete upgrade with no additional adapters or plumbing.----Direct fit for the 2020+ Chevrolet and GMC Duramax L5P 6.6L. No drilling, cutting, or modification required. Backed by the Mishimoto Lifetime Warranty.

Automatic transmission oil cooler designed to regulate fluid temperature and prevent overheating. Enhances transmission longevity, maintains performance, and features durable construction with a precise fit.

  • 245% larger core volume for serious heat dissipation - the oversized tube-and-fin core gives the transmission far more capacity to pull heat from the fluid under tow and heavy load.
  • Tube-and-fin aluminum core built for sustained load - durable all-aluminum construction holds transmission temps in check through the heat of towing where stock cooling falls short.
  • 173% more external fin area accelerates heat transfer - the added fin surface moves thermal energy from the fluid into the airstream far more efficiently than the stock cooler.
  • Factory connections, no adapters required - the cooler uses the OEM transmission line connections for a complete bolt-on upgrade with no extra fittings or plumbing work.
  • 137% more frontal area catches more cooling airflow - the larger frontal core area puts more of the cooler in the incoming airstream to drop fluid temps faster.
  • Drops in without modification - confirmed direct fit for 2020+ Chevrolet and GMC Duramax L5P 6.6L trucks, with no cutting, fabricating, or adapter work required
  • Own it for life - backed by Mishimoto’s Lifetime Warranty, your investment is protected long after install day.



Mishimoto 2020+ Chevrolet / GMC Duramax L5P 6.6L Transmission Cooler

$350.95

  • ACHIEVING

    4.8

    average rating

  • With

    95%

    positive reviews

  • LESS THAN

    3%

    return rate

Does it come with a warranty?

Yes, most products we sell are backed by the manufacture's warranty. Warranty coverage varies by brand, so check the product listing or contact us if you have any questions before purchasing.

What happens if I don't like it?

If you're not completely satisfied, we're here to help. Eligible unused items may be returned within 30 days of delivery, subject to our return policy and applicable restocking fees.

How fast is shipping?

We process most orders within 1-2 business days. Shipping times vary by product availability and location, but most customers receive their orders within 3-7 business days after they ship.

What's the returns policy?

Returns must be requested within 30 days of purchase, Items must be new, unused, and in their original packaging. Approved returns are subject to a 30% restocking fee. Custom order, electrical, and special order items may not be eligible for return.

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