Cummins B6.7, L9 DOC Filter 2018-2024: OEM 4395112

Durable Exhaust Treatment for Cummins B6.7 & L9 Engines (2018–2024)

What is it?
The Diesel Oxidation Catalyst (DOC) filter for Cummins B6.7 and L9 engines (model years 2018–2024), with OEM reference 4395112, is an essential emissions-control component. It converts hydrocarbons (HC) and carbon monoxide (CO) in the exhaust stream into cleaner, less harmful gases, helping the aftertreatment system maintain smooth and dependable operation.

Why choose this DOC Filter?
Engineered to match original equipment specifications for both B6.7 and L9 engine platforms, this DOC filter offers precise fitment and dependable integration with the exhaust and aftertreatment system. A mismatched, worn, or blocked filter can contribute to elevated exhaust restriction, frequent regeneration cycles, or emissions-related fault codes. Installing the correct DOC filter supports consistent exhaust flow and dependable emissions-system behavior.

Key Benefits
✅ Converts HC and CO into cleaner exhaust output
✅ Supports proper function of downstream aftertreatment components
✅ Helps maintain steady exhaust flow and reduce restriction
✅ Direct-fit design — no modifications required
✅ Built for heavy-duty, high-temperature operating environments

Applications
Ideal for medium- and heavy-duty trucks, commercial vehicles, and equipment powered by Cummins B6.7 or L9 engines from model years 2018 through 2024. This DOC filter is particularly suited for fleet, vocational, and on-road applications where consistent emissions control and reliable system performance are essential.

Installation Notes
Before beginning service, ensure the exhaust and aftertreatment system has fully cooled. Remove the existing DOC filter and inspect adjacent exhaust piping, sensors, and mounting hardware for soot buildup, cracks, or signs of wear. Install the replacement using fresh clamps, gaskets, and seals. After installation, clear any stored emissions-system fault codes and verify proper exhaust system behavior using diagnostic checks.

Final Thoughts
If your B6.7- or L9-equipped vehicle is showing signs of elevated exhaust restriction, frequent regeneration cycles, or emissions-related alerts, replacing the DOC filter with the correct OEM-specified unit is a practical way to restore clean, dependable exhaust flow. This component plays a vital role in maintaining the integrity of your emissions-control system and supporting reliable operation.