Cummins B6.7, L9 SCR 2018-2021: OEM 5418652

Engine-Matched NOx Control Module for Cummins B6.7 & L9 Engines (2018–2021)

What is it?
The Cummins B6.7/L9 SCR (Selective Catalytic Reduction) assembly, identified by OEM part number 5418652, is a critical emissions aftertreatment component used on Cummins B6.7 and L9 diesel engines manufactured between 2018 and 2021. Working with Diesel Exhaust Fluid (DEF), this module helps facilitate a chemical reaction that converts nitrogen oxides (NOx) in exhaust gases into nitrogen and water before they exit the aftertreatment system, contributing to regulated emissions control.

Why choose this SCR Assembly?
This SCR module is engineered to match Cummins’ original specifications for both B6.7 and L9 engine platforms, ensuring accurate fitment and dependable interaction with DEF delivery hardware, sensors, and engine control systems. Over time, SCR components may lose effectiveness due to normal wear or contamination, which can impact NOx conversion efficiency and trigger emissions alerts or variable exhaust behavior. Installing the correct OEM-specified SCR helps maintain consistent emissions performance and smoother system coordination.

Key Benefits
✅ Designed specifically for Cummins B6.7 and L9 aftertreatment systems (2018–2021)
✅ Helps sustain reliable NOx reduction with DEF interaction
✅ Supports coordinated operation with related emissions components
✅ Direct-fit replacement — no alterations required
✅ Built to withstand heavy-duty exhaust environments

Applications
This SCR assembly is suitable for medium- and heavy-duty trucks and commercial equipment powered by Cummins B6.7 or L9 engines built between 2018 and 2021. Typical use cases include delivery fleets, vocational trucks, regional transport rigs, and other commercial platforms where dependable emissions control and compliance are integral to daily operation.

Installation Notes
Before servicing, make sure the exhaust and aftertreatment system has fully cooled. Remove the existing SCR assembly and inspect adjacent DEF lines, sensors, and mounting hardware for wear, soot buildup, or damage. Install the replacement SCR module using proper seals and fasteners to ensure a secure, leak-free fit. After installation, clear any stored system codes and verify correct aftertreatment performance with diagnostic tools.

Final Thoughts
If your Cummins B6.7 or L9-equipped vehicle is showing NOx-related alerts, inconsistent emissions readings, or irregular aftertreatment behavior, replacing the SCR unit with the correct OEM-specified component can help restore balanced emissions control. The Cummins B6.7/L9 SCR (OEM 5418652) plays a key role in managing regulated exhaust chemistry and supporting reliable vehicle operation across a variety of duty cycles.