Hi this is just my story of what happened to me today I was on the road and I started to hear this tick me being the optimums thinking it was just my tappets and all i need was a little oil, my truck has a little oil leak so this happens every so often, so I pull over at a gas station grab a quart put it in her and carry on. then about 20mi later the noise come back but louder then a few seconds after I hear the noise again I heard a loud thud to tell the truth I was scared I thought I threw a rod or piston but thank god it was not that bad it was bad though apparently the bolts that hold on the crankshaft pulley onto the harmonic balancer have been falling out or some one sabotaged me. anyway I am siting on the highway with no engine or serpentine belt that what that was the loud thud was my belt slapping my hood when the pulley finally failed. so moral of this story check those bolts on your crank shaft pulley every so often it was something i never thought about doing but now i will.
thought id give a picture of the pulley