Hi Folks... been chasing this noise for a while and I finally got a second set of hands to help record the noise. @ncavi rev'd the truck for me, just as it leave idle and feels some load it makes that light knocking noise.
The noise seems heat dependent, and the frequency doesn't change much with rpm. A heat soaked engine, maintaining speed (~45mph) on flat ground, will make that noise constantly and it sounds like a can of change rattling around. (this thread discusses the same noise, but my heat shields and fan clutch seem solid, and my video below really sounds like it's something piston relatated)
Thoughts?
The noise seems heat dependent, and the frequency doesn't change much with rpm. A heat soaked engine, maintaining speed (~45mph) on flat ground, will make that noise constantly and it sounds like a can of change rattling around. (this thread discusses the same noise, but my heat shields and fan clutch seem solid, and my video below really sounds like it's something piston relatated)
Thoughts?