Nissan
mentioned grille shutters, a tow hook cover, cab - to - bed seals, underfloor covers, and spoilers for the tailgate and roof (except regular cab) contributing to better highway consumption, but the windshield rake and leading edge of the roof look to do their part as well.
The active
grille shutters, and some of the other feature
mentioned are carryover from the previous Ram, but they're interesting nonetheless.