I have a 2000 F150 with the 5.4 L. At start up the motor rattles a bit. It goes away after a short while and never presents itself during normal running. I spoke with a Ford mechanic, and he said it's piston knock and that it was nothing to worry about. Anyone else experience this problem?

 

In the mornings from start up and for the first mile or so can hear a very slight knock, but goes away and never gives any issues otherwise. It seems to be a rather common ailment with this motor.

2003 f150 Scab 5.4