I have a 2013 F150 Ecoboost. It started making a low sort of chugging /grinding noise when I either have a load in tow or gassing it going up hill. It is not always there and the we tried to replicate it at the dealer with no luck. The symptoms it creates is the chugging noise and the motor seems to chug as well. It does not change with RPM's, it is just a steady light sluggish noise and motor power. Anyone ever have this issue? It seems to be coming from the turbo.

 

Noises are difficult to resolve, especially on a forum. You might try posting a video/audio clip of the problem.