2003-2009 Cummins Fluidyne High-Performance Transmission Cooler (RT-48-0309)

A Line Kit is Required (you can find compatible Line Kits under Notes)

When it comes to protecting your transmission, cooling is key. Excessive heat is one of the biggest transmission killers, especially for hard-working trucks that tow, haul, or put power to the pavement

Why Cooling Matters: 

Heat breaks down transmission fluid, leading to premature wear, slipping, and even catastrophic failure. The factory transmission cooler is barely adequate for stock applications, add a tuned truck, heavy trailer, or extreme conditions, and you’re pushing your transmission’s limits. Fluidyne’s upgraded cooler is engineered to combat heat effectively, keeping your transmission fluid at optimal temperatures for maximum reliability and longevity.

Part Number: RT-48-0309

• Advanced Cooling Technology – Featuring a stacked plate design, this cooler offers three times the core area of traditional tube-and-fin coolers, allowing for superior heat dissipation. That means lower transmission temperatures, better performance, and increased transmission lifespan.
• Increased Fluid Capacity – With three times the fluid capacity of standard coolers, this system helps maintain stable operating temperatures under heavy loads, reducing the risk of overheating.
• No Thermostat, No Problems – Unlike some factory and aftermarket coolers, we do not include a thermostat. Why? Because thermostats can stick closed, preventing fluid from circulating and leading to overheating and potential transmission failure. By eliminating this weak point, Fluidyne’s cooler ensures unrestricted, consistent cooling.
• Built for Durability – Made from high-quality materials and tested in demanding conditions, this cooler is built to last, whether you’re towing cross-country, hitting the trails, or daily driving.
• Race-Proven Performance – Trusted in NASCAR and high-performance applications, Fluidyne cooling systems are engineered to withstand extreme conditions and deliver consistent results.
• Straightforward Installation – Designed for seamless integration with your 2003-2009 Ram 2500/3500, this cooler installs with minimal modifications, making it a hassle-free upgrade for any serious truck owner.

Compatible Line Kits:

• 48RE Line Kit without Heat exchanger
• 48RE Line Kit with Heat Exchanger

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