(parking,revering,idle)at low speeds motor drops to low idle & bad shakes/sounds

What is your question?

2009 Ford F150 5.4 Liter. Occurs at low idle rpm in gear. Feels and sounds like the engine is going to blow up and shake the truck apart. Also when warmed up usually 20 to 30 min of freeway, then when put in reverse or pulling into parking spot, drops to very low idle and sounds. Let off and go to neutral and rev a little and it goes away or accelerating till it’s no longer idling rough and shaking.

What makes this problem better or worse?

Let off gas and go to neutral and rev a little and it goes away or accelerate to speed

How long has your 2009 Ford F-150 had this problem?

A few months