I am not sure where the old thread went since last night, but I replaced the rattling O2 last night with another new one.....seems to be the first thing that has made any inkling of a change. It runs better now, but when I surprised it, the truck still bogged for a second. I will replace the other O2 tonight, and see what happens. I guess I waited so long to look at these as a possible culprit because I just bought them new in the Spring.