As most of you know I have lost 3 350 chevy engins in last 3 years. Firts origional engine when I got it droped valve. Oil problem I don't know. Do valves get lubed by oil? HUUMMMM. Second engine is a remanufactures motor from a supposally good rebuilder. Cam goes flat. Is this a luberacation problem? HUUMMMM. Same motor new cam 3 months later HOLE wore thru the rocker. Did I say HOLE thru rocker? What lubs rockers? Would you say lube problem? HUUMMM. Same engine new rocker 6 months later, droped valve distroyed motor. Would you say lub problem? What lubs valve guides? You guy's say what you want.I HAVE the expearance with oil problems and I think lack of ZDDP has caused my problems. Oh yea, did I say NO MORE PENNZOIL 30W after 20+ years. I'm talking to them about R&R of my motor. I'll keep you informed.