lilbit of everything

did you ever find your problem? have you checked the intake pressure sensor? This might sound crazy but make sure your coolant level is ok, and that the sensor is working. i have a cxu613, if the coolant level gets low it doesnt give me an engine light or derate code but it will reduce the torque by 40%..... Truck was driving me crazy, and couldnt figure it out, put water in it and Presto it pulled like it was supposed to