oh, we replace them here at our dealership, have seen a few for low end knock. Recently have replaced a couple for fuel contamination...customers love to hear that news....they just bought a engine, unless they can get the source of the fuel to poney up some dough. I will go in the recordbook as stating we dont replace near as many as FOrd or CHevy.
They are great engines 12 valve or 24 valve.
-RPM