Request help finding undercarriage gremlin!

[GLBLWARMR]

Over the last couple of days I have started to hear a vibration type noise in the center front end of my truck. The noise is best described as a lose heat shield. The noise occurs primarily when I have let off the gas when coming to a stop. It only lasts about a second or two.

I have checked the entire underneath for the cause but have been unable to locate. I went through and checked the tightness of anything that can be bolted down and everything seems in order. Has anyone else had this same noise/vibration?? If anyone has any insight I would be glad to have it.

Suspected perpetrator may look something like this: If you see him please let me know.

Russ