Effective Emissions Filtration for Cummins B6.7 & L9 (2018–2021)
What is it?
The Cummins B6.7, L9 DOC Filter OEM 4394859 is an essential emissions control element located within the Diesel Oxidation Catalyst (DOC) of your engine’s aftertreatment system. It works by oxidizing 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 emit cleaner exhaust.
Why choose OEM 4394859?
This DOC filter is specifically designed for Cummins B6.7 and L9 engines manufactured between 2018 and 2021. Its precise OEM engineering ensures dependable integration with your vehicle’s original emissions components, minimizing the risk of system faults and improving overall aftertreatment performance. With genuine OEM quality, you get durability and consistent emissions control.
Key Benefits
✅ Engineered for 2018–2021 Cummins B6.7 & L9 engines
✅ Helps reduce hydrocarbons and carbon monoxide in exhaust
✅ Enhances overall aftertreatment system function
✅ Built to withstand high-temperature exhaust conditions
✅ Direct-fit replacement for easy installation
Applications
This DOC filter is ideal for Cummins-powered trucks and equipment from 2018 through 2021. Typical uses include commercial trucks, vocational fleets, delivery rigs, and other diesel-powered machinery that depend on effective emissions control systems.
Installation Notes
Ensure the exhaust and aftertreatment system are fully cooled before beginning installation. Inspect nearby sensors, gaskets, and connections for wear or contamination. Follow Cummins-recommended installation procedures and torque specifications to ensure proper sealing and performance. After installation, verify that the emissions system is functioning correctly.
Final Thoughts
If your Cummins B6.7 or L9 engine is showing emissions-related alerts or diminished aftertreatment efficiency, the OEM 4394859 DOC filter provides a dependable, OE-grade replacement option. Built for accurate fit and consistent emissions control, it helps keep your engine compliant and running efficiently. Tamerx has this DOC filter in stock and ready to ship.