Cummins X15 SCR 2018-2021: OEM 5418634

Engine-Matched NOx Treatment for Cummins X15 Engines (2018–2021)

What is it?
The Cummins X15 SCR (Selective Catalytic Reduction) unit with OEM part number 5418634 is an emissions aftertreatment component designed for Cummins X15 diesel engines produced between 2018 and 2021. Working with Diesel Exhaust Fluid (DEF), this assembly supports a chemical process that transforms nitrogen oxides (NOx) in the exhaust into nitrogen and water before the gases exit the system, helping the engine meet emissions requirements.

Why choose this SCR Assembly?
This SCR module is built to Cummins’ original specifications for the X15 platform, ensuring precise fitment and reliable interaction with DEF delivery hardware, emission sensors, and engine control systems. Over time, SCR performance can diminish due to normal wear or contamination, which can reduce NOx conversion efficiency and potentially trigger emissions alerts. Installing the correct OEM-specified SCR helps maintain consistent emissions control and coordinated aftertreatment behavior.

Key Benefits
✅ Designed specifically for Cummins X15 aftertreatment systems (2018–2021)
✅ Helps support dependable NOx conversion using DEF
✅ Promotes steady operation alongside related emissions components
✅ Direct-fit replacement — no modifications required
✅ Built for enduring heavy-duty exhaust environments

Applications
This SCR unit is suited for heavy-duty trucks and commercial vehicles equipped with Cummins X15 engines built between 2018 and 2021. It’s commonly found in long-haul tractors, regional transport rigs, vocational trucks, and other commercial platforms where dependable emissions control and regulatory compliance are essential to daily operation.

Installation Notes
Before performing service, ensure the exhaust and aftertreatment system is fully cooled. Remove the existing SCR unit and check surrounding DEF lines, sensors, and mounting hardware for signs of wear, soot buildup, or damage. Install the replacement SCR assembly using correct seals and fasteners to ensure a secure, leak-free fit. After installation, clear any stored system codes and verify proper operation with diagnostic checks.

Final Thoughts
If your Cummins X15-equipped vehicle is experiencing NOx-related alerts, inconsistent emissions readings, or irregular aftertreatment behavior, replacing the SCR assembly with the correct OEM-specified part can help restore more balanced exhaust treatment. The Cummins X15 SCR (OEM 5418634) plays an important role in regulating exhaust chemistry and supporting dependable vehicle performance.