Fluidyne Heavy Duty Transmission Cooler – 03-05 LB7/LLY Duramax

$993.05

Fluidyne transmission cooler kit to suit the Heavy Duty – 03-05 LB7 / LLY Duramax. Drops ATF temperatures to protect your automatic under towing and heavy loads. Imported to order and backed by the team at Willys Workshop.

Imported to order — through our workshopWe bring this in from our supplier and receive it at our workshop first. From there we can build, tune or fit it for you — or ship it straight to you or your mechanic. Freight and any workshop work are quoted on enquiry.

Available to order

SKU: RT-A1-0305 Categories: , Brand:
Easy returns within 14 days
12 Month Warranty
Tuning & Fitment Available

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Easy returns within 14 days

12 month 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

INTRODUCTION TO FLUIDYNE EXTREME DUTY BAR PLATE TRANSMISSION COOLERS – YouTube

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INTRODUCTION TO FLUIDYNE EXTREME DUTY BAR PLATE TRANSMISSION COOLERS Randy's Transmissions

Randy's Transmissions22.3K subscribers

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Imported to Order — Through Our Workshop

  • Brought in from our supplier and received at our Sunshine Coast workshop first.
  • From there we can build, tune or fit it for you, or ship it on to you or your mechanic.
  • Freight and any workshop work are quoted on enquiry — international freight, customs and delivery vary by item and destination.
  • Typical lead time is confirmed at the time of order.

Get a freight + build quote: call (07) 5619 7869 or email sales@willysworkshop.com.au.

Additional information

Weight 8.16 kg
Dimensions 50 × 40 × 20 cm

Randy's Transmissions — Limited Warranty

Randy's Transmissions warrants all reman transmissions, torque converters and serviced components per the published Randy's Limited Warranty:

  • 12 months / unlimited km on reman transmissions (street use)
  • Lifetime on Randy's hard parts (gears, shafts) where stated
  • Claims processed via Randy's Warranty Claims & Support form
  • Original proof of purchase required
  • Competition / off-road use excluded unless specifically stated

Fitment by Willys Workshop can be arranged in-house at our Oxley or Warana locations — workshop fitment receipts count toward warranty claim documentation.

Read the full Randy's Transmissions warranty terms →


Warranty claims are coordinated through Willys Workshop. Email sales@willysworkshop.com.au or call Warana (07) 5619 7869 / Oxley (07) 3377 3421 with your order number and a description of the issue.

Questions, or need a fitment check?
Send your rego or VIN and our Australian-based team will manually confirm fitment before you buy.
Prefer to text your rego/VIN? 0485 885 957