This is the worst review that I have seen so far on the Titan diesel. I hope that it is an isolated case: http://www.caranddriver.com/reviews/2016-nissan-titan-xd-long-term-test-review
Seems to be all too common with diesel pickups. What is really annoying is with all the computer "gadgetry", they are still not smart enough to tell the techs what the problem is. Throw in the typical lack of engineering principles used to write software, and a you have real recipe for issues. My F250 has had a couple of instances of clogged DPF and limp mode issues that nobody seems to be able to diagnose.