Hi atpujol,I am having a low type horn/hum noise on it seems like the passenger side of my 2014 ecoboost. It has 16k miles. I just noticed it as it has gotten colder (is it the cold doing it?) its kinda random, but usually only last a second or two around 1500 to 2000 RPM in 2nd and 3rd gears. It sounds really similar to those 2 ft long plastic blow horns at soccer or football games that people have. It was a little louder when I was towing 7000# last weekend, but only happened twice off stop lights. Please help a otherwise very happy Ecoboost owner! Is this a problem? Thanks so much.
I'd bring this noise to the attention of your local dealership. When you drop off your truck, be sure to either mention the circumstances under which it happens or take your tech on a test drive. Come back and tell us what the dealer finds; I'll be here if you need any assistance.