Cummins ISB, QSB 4.5L, QSB 6.7L SCR Outlet Catalyst Module 2013-2016: OEM 4353066

Maintaining Consistent SCR Treatment in Cummins ISB & QSB Engines (2013–2016)

What is it?
The Cummins ISB, QSB 4.5L, and QSB 6.7L SCR Outlet Catalyst Module, identified by OEM 4353066, is an emissions aftertreatment component designed to support the final stages of Selective Catalytic Reduction (SCR). During this process, Diesel Exhaust Fluid (DEF) helps create the chemical conditions needed for the catalyst to convert nitrogen oxides (NOx) primarily into nitrogen and water vapor before treated exhaust exits the system.

Why choose this SCR Outlet Catalyst Module?
The SCR catalyst must maintain effective chemical activity and unrestricted exhaust flow to support proper emissions treatment. OEM 4353066 is intended for compatible Cummins ISB, QSB 4.5L, and QSB 6.7L applications from 2013 through 2016, helping maintain the correct configuration within the existing aftertreatment system.

Prolonged exposure to high temperatures, DEF deposits, soot, oil contamination, and repeated operating cycles can gradually affect the catalyst. Problems with DEF dosing, engine combustion, or upstream aftertreatment components can also contribute to premature deterioration.

Common indications of SCR-related problems may include emissions fault codes, increased NOx readings, warning lights, DEF system alerts, or irregular aftertreatment operation. Replacing a compromised module helps restore the intended exhaust treatment pathway.

Key Benefits
✅ Designed for compatible Cummins ISB, QSB 4.5L, and QSB 6.7L applications (2013–2016)
✅ Supports proper SCR exhaust treatment
✅ Helps reduce nitrogen oxide (NOx) emissions
✅ Supports conversion of NOx into nitrogen and water vapor
✅ Maintains proper integration with compatible DEF system components
✅ Designed for demanding diesel exhaust temperatures and operating cycles

Applications
This SCR Outlet Catalyst Module is intended for compatible Cummins ISB, QSB 4.5L, and QSB 6.7L diesel engine applications from 2013 through 2016. These engines may be found in commercial vehicles, buses, construction machinery, agricultural equipment, industrial equipment, and other diesel applications equipped with compatible SCR systems. Confirm OEM number 4353066 and engine-specific fitment before installation.

Installation Notes
Allow the exhaust system to cool completely before beginning installation. Inspect the DEF injector, decomposition section, NOx sensors, temperature sensors, exhaust connections, clamps, seals, and upstream aftertreatment components for deposits, leaks, contamination, or damage. Correct any underlying DEF, engine, or exhaust issue that may have contributed to catalyst failure. After installation, check for exhaust leaks, clear applicable diagnostic codes, and verify SCR operation using suitable diagnostic equipment.

Final Thoughts
A properly functioning outlet catalyst helps complete the chemical treatment required to control NOx emissions. The Cummins ISB, QSB 4.5L, QSB 6.7L SCR Outlet Catalyst Module (OEM 4353066) provides application-specific compatibility for maintaining dependable SCR operation in qualifying 2013–2016 applications.