Today I got into my truck in the morning to make a short trip to my father in laws house about 6 miles away. By the time I arrived the truck was just about up to normal operating temperature. When I got out with the truck idling, I immdiately heard a tapping, ticking sound coming from what sounded like the rear of the engine. I just had the oil changed yesterday at Ford, at 2300 miles. Well called my service tech and he told me to stop in so he could hear it! Needless to say about a half hour of driving later the noise stopped. I've heard of this happening to these new engines, but does anyone know WHY?