DEF Headers

At American Radiator, we supply the DuraWRX™ DEF Header, the key component that keeps your diesel exhaust fluid (DEF) system efficient, reliable, and compliant with EPA emissions standards. Many ask: What does a DEF Header do? It monitors DEF level, concentration, and temperature while protecting engines from cold-weather shutdowns. Designed with ultrasonic sensing technology, this solid-state header eliminates failures common with mechanical sensors, delivering precise, dependable data to leading dosing units in modern SCR (Selective Catalytic Reduction) systems.

Cold weather presents a serious challenge since DEF can freeze at low temperatures. To solve this, the DuraWRX™ DEF Header integrates an engine-coolant powered heater that thaws DEF even at -40°F (-40°C), ensuring trucks and equipment remain compliant and operational in extreme conditions. Built to meet strict OEM and government regulations, it’s the trusted choice for Freightliner, Cummins, International, and heavy-duty fleet applications.

For added flexibility, American Radiator offers optional DEF accessories such as remote fill adapters, lockable caps, coolant control valves, electrically heated hoses, and mounting brackets. When you need the best DEF Header replacement or a proven DEF freeze prevention solution, trust American Radiator to deliver durability, compliance, and performance.