My 2012 was built with the top shield on it.Do TSB's like this get applied on the production line once they are released? i.e... if my truck is built in the next month, will it come with the top or the new bottom air deflector??
Have you checked your spark plug gaps?Had this happen to me for the second time today. 2013 FX4. Driving in the rain from Miami to Tampa, noticed the mileage was dropping from around 19.5 down to around 18, accelerated from about 75 mph hard enough to have the tranny downshift to 5th, engine lost power, check engine light started flashing, felt like it was missing on several cylinders. After about 1 minute, it cleared and was fine for balance of trip.
Interesting that it happened the same way several weeks ago on the same trip in the same conditions. I had been driving at 75mph for about 3 hours both times.