Cummins ISB, QSB 4.5L, QSB 6.7L SCR Outlet Catalyst Module 2010-2012: OEM 4353066

Supporting Final-Stage Exhaust Treatment in Cummins ISB & QSB Engines (2010–2012)

What is it?
The Cummins ISB, QSB 4.5L, and QSB 6.7L SCR Outlet Catalyst Module, identified by OEM 4353066, is an aftertreatment component designed to support the Selective Catalytic Reduction (SCR) process. Within the SCR system, Diesel Exhaust Fluid (DEF) reacts with exhaust gases so nitrogen oxides (NOx) can be converted primarily into nitrogen and water vapor before the treated exhaust leaves the system.

Why choose this SCR Outlet Catalyst Module?
Effective SCR operation depends on the catalyst maintaining the correct conditions for NOx treatment. OEM 4353066 is intended for compatible Cummins ISB, QSB 4.5L, and QSB 6.7L applications from 2010 through 2012, helping maintain proper integration with surrounding aftertreatment components.

High exhaust temperatures, DEF deposits, contamination, physical damage, and extended operating cycles can gradually affect the catalyst. Engine problems that introduce excessive oil, fuel, or soot into the exhaust may also shorten its usable life.

Possible signs of a deteriorating SCR catalyst include emissions-related fault codes, elevated NOx readings, warning lights, DEF system concerns, or irregular aftertreatment operation. Installing the correct application-matched module helps restore the intended exhaust treatment process.

Key Benefits
✅ Designed for compatible Cummins ISB, QSB 4.5L, and QSB 6.7L applications
✅ Supports final-stage SCR exhaust treatment
✅ Helps reduce nitrogen oxide (NOx) emissions
✅ Supports conversion of NOx into nitrogen and water vapor
✅ Integrates with compatible DEF and aftertreatment components
✅ Designed for demanding diesel exhaust temperatures and operating conditions

Applications
This SCR Outlet Catalyst Module is intended for compatible Cummins ISB, QSB 4.5L, and QSB 6.7L diesel engine applications from 2010 through 2012. These engine families may be used 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 components, NOx sensors, temperature sensors, exhaust connections, clamps, seals, and nearby aftertreatment components for deposits, contamination, leaks, or damage. Correct any underlying engine or DEF system issue that may have contributed to catalyst deterioration. After installation, inspect for exhaust leaks, clear applicable diagnostic codes, and verify SCR system operation with suitable diagnostic equipment.

Final Thoughts
Consistent NOx treatment depends on proper DEF delivery and a catalyst capable of completing the SCR process. The Cummins ISB, QSB 4.5L, QSB 6.7L SCR Outlet Catalyst Module (OEM 4353066) helps maintain reliable exhaust treatment for compatible 2010–2012 applications.