Cummins ISB 6.7 DOC

Restore Clean Exhaust Flow with the Cummins ISB 6.7 DOC

What is it?
The Diesel Oxidation Catalyst (DOC) for the Cummins ISB 6.7 engine is a critical emissions-control component. It oxidises hydrocarbons (HC) and carbon monoxide (CO) in the exhaust gas stream into cleaner, less harmful by-products, supporting the after-treatment system in functioning reliably.

Why choose this DOC?
Engineered specifically for ISB 6.7 (model years 2014-2017), this DOC meets factory design specifications and ensures correct fitment, appropriate exhaust-gas flow characteristics, and durable construction. A worn or restricted catalyst can lead to elevated exhaust restriction, repeated regeneration events, or emissions-related fault codes. Installing the correct DOC helps restore stable system behaviour and clean exhaust flow. 

Key Benefits
✅ Converts HC and CO into cleaner exhaust output
✅ Maintains proper exhaust-gas flow characteristics for downstream components
✅ Helps reduce resistance in the exhaust path and supports system stability
✅ Direct-fit design—no modifications required
✅ Designed for heavy-duty use and extreme exhaust-temperature environments

Applications
Ideal for medium-duty trucks, vocational vehicles, buses and other equipment powered by the Cummins ISB 6.7 engine (2014-2017 model years). It is especially beneficial in operations requiring consistent emissions control and dependable system performance. 

Installation Notes
Allow the exhaust system and emissions-aftertreatment components to cool completely before service. Remove the existing DOC, clean the mating surfaces carefully, and inspect surrounding hardware for soot build-up, leaks or damage. Install new gaskets, clamps, and seals as required, and mount the replacement DOC with correct torque and orientation. After installation, clear any emissions-system fault codes and verify through diagnostics that the exhaust system flows correctly and no leaks are present.

Final Thoughts
If your ISB 6.7-equipped machine is showing emissions warnings, increased exhaust restriction, or inconsistent after-treatment behaviour, replacing the DOC with a properly matched unit is a practical step to restore clean, dependable exhaust flow. This component is crucial in maintaining the integrity of the overall emissions system and supporting reliable operation.