Derale 14210 Finned Cooling Transmission Pan 47RE/48RE

The Derale 14210 is a deep cooling pan for the Dodge A518 (46RH/46RE) and A618 (47RH/47RE/48RE) transmissions, the units behind a lot of Ram trucks and the 5.9L Cummins. It is stamped from heavy-gauge steel with cooling fins pressed into the bottom and sidewalls, then finished in a two-stage heat-dissipating black coating. The fins and the extra surface area pull heat out of the ATF, and the deeper sump holds more fluid than the flat factory pan, so the transmission carries a lower steady temperature when you are towing, hauling, or sitting in traffic on a hot day.

Heat is what kills these transmissions. The 47RE and 48RE cook their fluid and clutches when a stock-depth pan runs low on capacity behind a loaded truck, and once the ATF breaks down the overdrive and lockup clutches are next. Adding fluid volume and shedding heat at the pan is one of the cheapest things you can do to keep a working truck out of the shop.

The pan has a 1/8 inch NPT port cast into it for a temperature sender, so you can run a real pan-temperature gauge and actually watch what the fluid is doing instead of guessing. That port is the difference between catching a hot tow before it damages anything and finding out after. The heavier steel also stiffens the bottom of the case and resists the flange flex that makes thin stock pans seep at the gasket.

Check clearance before you order. On some 3/4 and 1-ton chassis the crossmember sits close to the sump, so on a lowered or heavily loaded truck confirm crossmember and exhaust clearance, and plan to reuse a good gasket and filter. Torque the pan bolts evenly in a cross pattern so the new pan seals flat.