Diesel heavy duty engines release more toxic substance in the air. This can be easily explained because they have long working hours, bigger consumption, bigger displacement and all that results with bigger amount of diesel smoke which comes through the exhaust.

Cummins engines for heavy duty trucks to meet emission regulation have unique aftertreatment system which comes as a part of the exhaust system as proprietary package which combines DPF (Diesel Particulate Filter) and SCR-technology to remove up to 90% of the particles which are leaving the engine after the diesel fuel is burned.

The beauty of this aftertreatment system is that it gives excellent results in the toughest conditions where is tested and also because of the fact that is in house designed allows Cummins to calibrate the heavy duty engines for optimized fuel economy.

The engine’s exhaust gas first enters in DPF which capture the soot particles. Most of the time the DPF cleans itself by oxidizing the particulate matter through passive regeneration or active regeneration.

SCR or selective catalytic reduction, uses wall-flow-substrates to detect and capture the exhaust gas and remove PM. This on short what you need to know about the structure of the aftertreatment system and what it actually does.

Most of the time if you are heavy duty truck driver these systems don’t require any manual actions from you but when that is needed some signal on the dash will notify you what you need to do. This varies from manufacturer to manufacturer but when the signal is on there is nothing you can do, it’s just for your information. How beautiful isn’t it, you don’t need to do anything.

On the video below is included a lot more information and what the exact process is and when the active regeneration is taking place or the passive one. Watch the video and see what you need to know and how to react.