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Randy's Transmission

FLUIDYNE HEAVY DUTY TRANSMISSION COOLER – 03-05 LB7/LLY DURAMAX

SKU: RT-A1-0305

$459.00

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HEAVY DUTY BAR-PLATE COOLER

2003-2005 LB7/LLY DURAMAX

Over 4x cooling efficiency over stock/oem

Up to 20° Lower Temps

Limited Lifetime Warranty

Description

Upgrade your transmission cooling system with the Fluidyne High Performance Bar and Plate Transmission Fluid Cooler, engineered for the 2003-2005 GM 6.6L Duramax. This advanced cooler provides over four times the heat dissipation capability compared to factory models, ensuring optimal transmission temperatures and enhanced efficiency.

Why Cooling Matters:
Heat is a major enemy of transmission longevity. For your 2003-2005 Chevy/GMC 6.6L Duramax, whether used for towing, fleet duties, or performance driving, maintaining optimal transmission temperatures is crucial.

Advanced Bar and Plate Design:
The Fluidyne cooler features a heavy-duty bar and plate design, Featuring the highest density of fins per inch on the market- offering superior durability and cooling efficiency. This design outperforms the stock unit by significantly increasing both core volume and fin surface area—193% more. This means better heat dissipation and improved transmission performance.

Larger and More Efficient:
Our cooler is designed to be substantially larger than the stock cooler, providing enhanced cooling capacity. The increased core volume and fin surface area help ensure your transmission stays within the optimal temperature range, even under heavy loads.

Built to Last:
Constructed with aerospace-grade aluminum, the Fluidyne cooler is engineered for maximum durability. TIG welding ensures a robust and leak-free construction, while fully welded internal splitter plates prevent fluid contamination. Pressure tested to 250 psi, it can handle extreme conditions with ease. Additionally, the cooler is powder-coated with a specialized heat-wicking compound and features a proprietary fin design to enhance thermal performance.

Easy Installation:
The Fluidyne cooler features pipe thread connections, offering a wide variety of connecting solutions to best fit your needs. It comes with CNC-machined adapters for a seamless, leak-free connection to your existing transmission lines or fully custom lines. Its your truck; customize it the way you want. 

Lifetime Warranty:
We stand by the quality of our product with a Lifetime Warranty. This guarantees worry-free performance and peace of mind for as long as you own your truck.

Key Features:

  • Over four times the heat dissipation capacity compared to stock coolers
  • Direct bolt-in replacement
  • Maximum fin density for optimal cooling
  • Fully welded internal splitter plates to prevent fluid contamination
  • Tested up to 250 PSI against leaks and ensure optimal performance. 
  • Aerospace-grade aluminum construction with bar and plate design
  • Proprietary fin design for enhanced thermal performance
  • Powder-coated with a specialized heat-wicking compound
  • Easy installation using factory mounts
  • Limited lifetime warranty

📌 Before You Complete Your Purchase — please review the important information below regarding product accuracy, pricing, inventory, and return policies.

Terms & Conditions

While we strive for accuracy, FrankBUILT Performance does not warrant that product descriptions, prices, or other content is error-free. Prices are subject to change without notice. In the event of an error, we reserve the right to cancel or correct any order. Inventory availability is not guaranteed.

Shipping & Returns

It is the customer's responsibility to verify product fitment before placing an order. If you receive the wrong item due to an error in our listing, we will work to resolve the issue. Returns may be subject to a restocking fee. Items must be unused and in original packaging.

2-Year Warranty

FrankBUILT transmissions only - unlimited miles

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