Dieselsite Coolermax Transmission Cooler

DieselSite COOLERMAX Transmission Cooler – High Efficiency Universal Upgrade

Extend the life of your transmission efficiently and economically with the DieselSite COOLERMAX Transmission Cooler. Designed to dramatically reduce transmission fluid temperatures, this cooler is an ideal upgrade for towing, stop-and-go driving, and high-load applications where heat is the #1 transmission killer.

🔥 Why Transmission Cooling Matters

Automatic transmissions fail by the thousands every year due to overheating. Once fluid temperatures climb, damage accelerates rapidly:

• 200°F – Fluid begins to break down

• 240°F – Varnish forms; transmission life is cut in half

• 260°F – Seals and rubber components harden; major damage begins

• 295°F+ – Slipping, burned clutches, and carbon buildup

💡 Every 20°F drop in operating temperature can double transmission and fluid life.
Reducing temps by up to 60°F can mean the difference between years of service and an early rebuild.

🛠️ The DieselSite COOLERMAX Solution

The COOLERMAX Transmission Cooler is engineered to outperform factory coolers and many aftermarket options. It can be used as a direct replacement or as an auxiliary cooler in addition to your OEM unit.

🔥 Key Features & Specs:

• -8AN inlet size

• 59,000 BTU cooling capacity

• 17-row stacked plate core for maximum heat transfer

• Core size: 22.85" x 7.25" x 1.25"

• 150 PSI working pressure / 750 PSI burst pressure

• Fin-and-plate design – combines stacked-plate efficiency with fin cooling

• JIC fittings with 316 stainless hose barb adapters for corrosion resistance

• Universal mounting brackets – mount anywhere space allows

• Same bracket footprint as Tru-Cool® 4739, with 10,000+ additional BTUs

⚙️ Installation Flexibility

• Cooler can be mounted up, down, or sideways

• Optimal orientation: fittings facing up

  • Ensures all air is purged

  • Allows 100% of the cooler to be used for heat exchange

📦 Hardware Options

Choose the setup that fits your needs:

• Cooler Only – fittings included

• Installation Kit (Optional) includes:

  • 6 ft transmission hose

  • Menders & clamps

  • Zip-tie mounting kit

  • Mounting hardware

👉 Select fitting size based on your truck’s transmission line size.

🔍 Why COOLERMAX Outperforms Other Coolers

Most coolers fall into one of three designs:

• Tube & Fin – least efficient

• Stacked Plate – better heat transfer

• Fin & Plate (COOLERMAX) – combines both designs for maximum efficiency with minimal pressure loss

This design allows COOLERMAX to keep temperatures low even in heavy towing and stop-and-go traffic, without the need for electric fans.

✅ Bottom Line

If you tow, daily drive in traffic, or run added power, the DieselSite COOLERMAX Transmission Cooler is one of the smartest upgrades you can make. Lower temps mean longer transmission life, better performance, and peace of mind—all with a simple, proven solution.