2016 Ford F-150 special edition fx4. 2.7l with 24,000 miles. I have owned the truck for four month and there is a vibration and I believe it's gotten worse but it could be in myth head

The vibration is felt mainly in the pedals and the steering wheel. It is most prominant in higher gears (5/6) at about 1400 rpm although you can feel it other times but mostly in high gears and lower rpm. It is not a super consistant vibration. The weird part is,IF YOU LET OFF THE GAS THE VIBRATION STOPS INSTANTLY. It's not overwhelming but quite annoying and it definitely shouldn't be there. To me, with the slight inconsistency in it, it almost feels like when my coil packs/ plugs we're going bad in my 5.4l.

So far the ford garage has told me that only vibration they feel is from the tires. (Which makes no sense because it stops when you let off the gas). And they have said anything else seems like It's just between shift points and the turbo but... It doesn't seem like that.