i drove the truck today and the noise got louder and stared to sound more like a exhaust leak......... so i checked the manifold and the bolts were loose i was able to take one out by hand , so i replaces the gasket got the bolts tight and no more noise.
thanks every1

 

wow, you were able to take a manifold bolt out by hand, holy ****
mine has never pinged, now it will b/c i said that
our combine had the broken manifold bolt problem, you could only hear it when it was revved up