SKU: 21944039356

Dieselsite Coolermax Transmission Cooler

Sale price$99.00 Regular price$110.00
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Ships within 48 hours · Estimated delivery Aug 16 - Aug 21

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Description

Dieselsite Coolermax Transmission CoolerDieselSite 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

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.

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 21944039356

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Nilo s
Massapequa, US
★★★★★ 5
Fits well, sane quality as the oem installed
Works really well, it fits and matches the original spark plugs and very easy to install. Very affordable! It starts right up , quality is very good and didn't have to adjust the gap on spark plugs!
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Reviewed in the United States on July 5, 2025
S
Verified Purchase
Seth
Grantham, US
★★★★★ 5
Fresh Spark Plug for the Mowing Season
Just what my push mower needed! Very compatible with my Craftsman M220 push mower. It was the right replacement part and workings just like the original brand B&S plug. Gap was correct right out of the box as my push mower fired right up first pull. Would recommend for anybody with a Craftsman M220.
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Reviewed in the United States on April 14, 2026
M
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mike c.
Charlottesville, US
★★★★★ 5
Good spark
Good fit. Fired right up
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Reviewed in the United States on May 13, 2026
J
Verified Purchase
John Mooney
Pawtucket, US
★★★★★ 5
Good deal on spark plugs
They worked perfectly for me
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Reviewed in the United States on May 28, 2026
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Brett Patterson
Birmingham, US
★★★★★ 5
Better running mower
Seems to work fine and runs great
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Reviewed in the United States on May 15, 2026

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