COTC PACCAR MX-13 & Kenworth Truck Regeneration (‘ReGen’)

The trucking industry is heavily regulated; including engine emissions. The EPA requires emissions controls for semi-trucks burning ultra-low sulfur diesel (ULSD) in the form of particulate matter reductions.

Central Oregon Truck Kenworth’s come equipped with the PACCAR MX-13 engine. PACCAR developed the Engine After Treatment Systems (‘ATS’). The ATS is made up of the Diesel Particulate Filter (‘DPF’) System and the Selective Catalytic Reduction (‘SCR’) System to reduce particulate and nitrogen oxide emissions. When the soot level in the DPF exceeds the desired level, a regeneration is required.


“You shouldn’t have to manually regen your DPF. The ATS will automatically do a regen while you’re going down the road. However, excessive idle time will require a manual regen to be initiated,” said Phil Taylor, the VP of Maintenance at Central Oregon Truck.

Should you need to a manual regen Josh Laughlin, Maintenance Specialist, says “a manual parked regen will take approximately 10 minutes. A big thing to keep in mind is that even though it says 10 minutes the regen could run up to 1 hour and 45 minutes. The ATS is programmed to say 10 minutes. Every time this process is interrupted you will have to start from the beginning.”

The following steps are recommended for a parked manual regen:

  1. Pull the vehicle over to a safe location
  2. Ensure no one is in the immediate vicinity to the tail pipe
  3. Maintain a minimum of 5 feet of clearance to any combustible materials from the edge and top of the vehicle
  4. Make sure your jakes/exhaust brakes are off and cruise control is in the off position
  5. Make sure both of the parking brakes are set truck and trailer
  6. Push the button for 20 seconds to start the regen – the truck’s RPMs should raise. When the regen is done the RPMs will return to normal.