Effective Emissions Filtration for Cummins B6.7 & L9 Engines (2018–2021)
What is it?
The Cummins B6.7, L9 DOC Filter OEM 4394859 is an important emissions control component housed within the Diesel Oxidation Catalyst (DOC) of your engine’s aftertreatment system. It converts harmful exhaust pollutants—such as hydrocarbons and carbon monoxide—into less harmful compounds before they proceed through the rest of the system, helping your engine meet emissions requirements while running efficiently.
Why choose OEM 4394859?
Designed specifically for Cummins B6.7 and L9 engines produced from 2018 through 2021, this DOC filter offers precise fitment and seamless integration with the original aftertreatment setup. Its OEM-grade construction helps reduce system faults, maintain reliable performance, and ensure long-lasting emissions control. With genuine OEM quality, you’re choosing dependable durability.
Key Benefits
✅ Built for 2018–2021 Cummins B6.7 & L9 engines
✅ Helps reduce hydrocarbons and carbon monoxide in exhaust
✅ Promotes efficient aftertreatment system operation
✅ Constructed to withstand high-temperature exhaust conditions
✅ Direct-fit replacement for easier installation
Applications
This DOC filter is ideal for Cummins-powered commercial trucks, vocational vehicles, fleet rigs, and other diesel-powered machines built between 2018 and 2021 that depend on reliable emissions control for everyday performance.
Installation Notes
Ensure the exhaust and aftertreatment system are completely cooled before beginning installation. Inspect nearby sensors, gaskets, and connections for wear or contamination. Follow Cummins-recommended installation procedures and torque specifications to ensure a proper seal and performance. After installation, verify that the emissions system is functioning properly.
Final Thoughts
If your Cummins B6.7 or L9 engine is showing emissions-related alerts or reduced aftertreatment efficiency, the OEM 4394859 DOC filter delivers a reliable, OE-quality replacement. Designed for precise fit and consistent emissions control, it helps keep your engine compliant and operating smoothly. Tamerx has this DOC filter in stock and ready to ship.