DuraWRX DEF Header for Volvo/Mack 70L Tank, Digital CANbus Level Sensor, 22.5" is an OE-form replacement header assembly engineered for Volvo and Mack SCR systems with 70L tanks. This header integrates a digital CANbus level sensor and liquid handling interfaces in a single serviceable assembly to restore factory-level DEF level reporting and return-to-service faster than multi-component repair approaches. The assembly includes a 40 micron in-tank filter and SAE J2044 fluid fittings sized to match OE return and suction ports, minimizing hose rework and installation time. Solid-state ultrasonic sensing and digital output reduce the failure modes common to mechanical float sensors, while the cartridge-style filter and standardized electrical connector simplify field replacement and parts staging. For fleet operations, the unit is a direct-fit aftermarket option designed to match Volvo/Mack tank height and interface locations, enabling technicians to replace the failed head without tank removal in many service scenarios. Restoring accurate level readings prevents unnecessary service calls prompted by intermittent or false low-level indications and helps maintain predictable DEF refill intervals. The integrated design also reduces the number of individual components to track in parts inventory, which streamlines stocking and lowers the chance of extended downtime due to missing parts. Installation requires standard DEF system service practices and yields immediate restoration of level-sensor telemetry to the vehicle CAN network. The assembly is manufactured to aftermarket quality standards and is offered as a replacement for multiple Volvo and Mack OE cross-reference numbers for 70L applications. This product content is intended for procurement, technician guidance, and fleet maintenance planning where dependable DEF level sensing is required to maintain SCR system availability and accurate fluid management across heavy-duty trucks.