What the guy is speaking of, but doesn't fully understand is the DPF and EGR system which is required by EPA... its added to the invoice of the engine by the body builder as an EPA requirement... . not a penalty.....
You have the Cummins option as one price, and the EPA equipment as a second line number... . If you ordered the CAT option it would show the same way... . and if you were to look at the sticker of a Class 5-8 truck it would be the same... .