Why Transmission Cooling Matters

Heat kills transmissions. Plain and simple. Every year, trucks get sidelined—not because the engine gave up, but because the transmission cooked itself alive. You tow, you haul, you sit in traffic, and all the while your fluid is breaking down, seals are hardening, and clutches are begging for mercy.

At 200° your ATF starts to degrade. At 240° varnish is forming. Push to 260° and rubber internals are toast. Hit 295°? Game over. Slipping, burning, and the kind of repair bill that makes your wallet hurt worse than your truck.

The DIESELSITE Solution

Enter the DIESELSITE 17-Row COOLERMAX.

Rated at a monster 59,000 BTUs, this cooler doesn’t just compete—it sets the bar. Standard factory units limp along at 15k–30k BTU. Even most “heavy-duty” aftermarket coolers top out well below the COOLERMAX’s rating. That extra capacity can mean the difference between cruising safely at 180° or cooking at 240°. In the real world, that translates into drops of 50–60°, longer fluid life, and transmissions that simply last.

Built for Performance and Durability

The COOLERMAX isn’t just bigger—it’s engineered smarter. With a 17-row stacked-plate core for maximum surface area, -8AN inlets, 316 stainless adapters, and universal mounting brackets, this unit is made to take abuse and keep delivering.

Compared to anything else on the market, the COOLERMAX provides a massive margin of cooling reserve, so you’re not just “good enough”—you’re bulletproof.

Standard and Powerstroke-Specific Options

The DIESELSITE 17-Row COOLERMAX is built to fit your truck and your preferences. Buyers can choose cooler fittings only for a simple upgrade or opt for a complete installation kit that includes hoses, clamps, and hardware for a hassle-free setup. Both options are available with 3/8″ or 1/2″ fittings to match your truck’s lines. For enthusiasts running the popular 1994–2003 Ford Powerstroke, there’s a dedicated kit designed for a direct-fit, bolt-on installation, providing heavy-duty cooling for these legendary 7.3L and early 6.0L trucks right out of the box.

Versatility in Installation

Mount it up, down, or sideways. Run it standalone or in series with your OEM cooler. The COOLERMAX plays well with just about any setup, giving you unmatched flexibility.

Your cost? A fraction of what a transmission rebuild will run you.