Freightliner Detroit DD5, DD8, DD13, DD15 DEF Head Unit

Reliable DEF Monitoring for Freightliner with Detroit Engines — OEM DEF Head Unit

What is it?
The OEM DEF Head Unit is a factory-spec header assembly designed for Freightliner trucks powered by Detroit engines (DD5, DD8, DD13, DD15) that use Diesel Exhaust Fluid (DEF) systems. Mounted on top of the DEF tank, this unit houses sensors that monitor DEF fluid level, temperature, and works with the vehicle’s emission control system to regulate SCR (Selective Catalytic Reduction) performance.

Why choose this OEM DEF Head Unit?
Built to Detroit’s original standards, this head unit ensures accurate readings, proper sealing, and compatibility with factory wiring and diagnostics. Using the genuine component helps prevent warning codes, sensor faults, leaks, or performance issues commonly caused by inferior or mismatched replacements.

Key Benefits
 ✅ Direct-fit for Freightliner trucks with Detroit DD5 / DD8 / DD13 / DD15 engines
 ✅ Precise monitoring of DEF fluid level and temperature
 ✅ Sealed construction to prevent leaks and contamination
 ✅ Supports factory diagnostics and emission system presets
 ✅ Durable enough for long-term operation under heat, vibration, and road stress

Applications
This DEF head unit is intended for use in Freightliner vehicles using Detroit diesel engines (DD5 to DD15). It is vital for applications including regional delivery, vocational trucks, heavy-haul operations, and municipal duty cycles, where consistent DEF system function is required.

Installation Notes
Installation should be carried out by a qualified technician. Before beginning, ensure the DEF system is depressurized or isolated to prevent spills or sensor interference. Thoroughly clean the DEF tank opening and inspect the mounting surface for residue, corrosion, or physical damage. Any worn or compromised O-rings or gaskets should be replaced to maintain a proper seal. Carefully install the new DEF head unit and torque all fasteners to OEM specifications. After installation is complete, use diagnostic tools to verify sensor outputs, check for leaks, and clear any DEF or SCR-related fault codes to confirm proper system function.

Final Thoughts
If your Freightliner with a Detroit engine is experiencing DEF-level errors, sensor faults, or emission system warnings, replacing the update DEF Head Unit with the correct OEM version restores accuracy and system reliability. It ensures your SCR system functions as designed—helping your fleet stay compliant and running.