Derale 15300 16-Pass Tube and Fin Transmission Cooler Core

The Derale 15300 is the bare tube-and-fin cooler core used in Derale -8AN Electra-Cool remote cooler systems. It is a replacement core — the finned heat exchanger only, not a complete kit with fan, shroud, or mounting brackets. If your remote cooler core is bent, weeping at the tubes, or clogged after years of service, this is the part that drops back into the existing assembly.

Fluid makes 16 passes through the stacked tube-and-fin element, so ATF or engine oil takes sixteen trips across the airflow before it heads back to the transmission. Both ports are -8AN to match the lines already run on a Derale Electra-Cool remote setup. Because a remote core mounts away from the radiator where a fan can pull air straight through it, it drops fluid temperature faster than a small inline cooler crammed in front of the A/C condenser.

Heat is what kills an automatic. Fluid that runs 40 to 60 degrees cooler keeps its friction properties and does not varnish the clutch packs, so a cooler that genuinely sheds load-heat is cheap insurance on a tow rig or a built transmission. Confirm your current system uses the -8AN 16-pass core before ordering — this core is sized for that specific Electra-Cool platform, not a universal bolt-on cooler.