Activate Cleaner Flow with Cummins ISL9 DOC
What is it?
The Diesel Oxidation Catalyst (DOC) for the Cummins ISL9 engine transforms hydrocarbons (HC) and carbon monoxide (CO) in the exhaust into less harmful by-products. It’s a foundational part of your emissions system, prepping gases for downstream treatment.
Why choose this DOC?
Built for the ISL9 platform, this DOC delivers proper fit and dependable performance. A failing or restricted catalyst frequently causes elevated back-pressure, repeated regeneration attempts, or emissions-related fault codes. Installing the correct switch-out supports stable exhaust flow and system operation.
Key Benefits
✅ Converts HC and CO for improved exhaust emissions output
✅ Shields downstream DPF and SCR components from extra stress
✅ Helps lower back-pressure and reduce exhaust restriction
✅ Direct-fit installation—no modifications required
✅ Designed for heavy-duty, high-temperature service environments
Applications
Perfect for medium- and heavy-duty vehicles powered by the Cummins ISL9 engine, especially where emissions compliance and exhaust system performance are vital.
Installation Notes
Ensure the exhaust system has cooled fully before service begins. Inspect the DOC housing, clamps, connections, and mounts for damage or soot buildup. Replace any worn gaskets, seals, and clamps during installation. After fitting the new DOC, clear any diagnostics fault codes and monitor exhaust system behavior and after-treatment status via diagnostics.
Final Thoughts
If your ISL9 engine is showing signs of emissions system inefficiency—such as elevated back-pressure, frequent regeneration cycles, or fault codes—upgrading the DOC with this target-fit unit is an effective step. With correct fitment and built-to-last construction, this part assists your engine in running cleaner, smoother, and reliably.