Here is another thought... I'd be interested in seeing how Nissan dealers would handle a diesel motor all of a sudden. Ie, diesel mechanics and diesel service... . At least Dodge/Ram dealers are already use to having diesel trucks to work on and to know. I personally would be needing some hard convincing to go to my local Nissan Dealer for a diesel pickup (even if it was a Cummins) I already have a very good confort level with my Dodge/Ram dealer in regards to diesel trucks. My local nissan dealer is crap...
A good point. There would be a steep learning curve to get people trained and lots of expensive service department software that manufacturers would demand dealers purchase. Many Dodge dealers still don't have real diesel mechanics after all these years.