I am a first itme diesel owner as of July. My truck is a 2013 3500 duramax with 57,000 miles on it. Recently it pulled a NOx code. Teh diesel shop I am taking it too said new sensorts are $370 a piec...
I replaced a bad NOX sensor on my Ram this summer. Cost about $250 for the part on Amazon and it took 20 minutes. You might look into just replacing the sensor yourself. You will need to figure out if the upstream or downstream sensor is throwing the code.