Alright, here is the deal..... A few months ago I pulled my engine out (less than 5k miles on it, its a GM 350HO). There was a broken skirt on a piston, I replaced the piston, GM parts guy said he thought it was just bad casting. Well, now the kock is back. I have pulled off the oil pan, and it looks like a skirt might be broken off again, except I can't remember which piston I replaced (stupid I know), it might be the one that is broken again, I'm not sure. The thing is though the "break" on it looks so clean and straight, like it suppose to be there, but I don't think it is. I also can't find the piece. I didn't find the piece of the other one though until I had the enigne out for a few days and had taken it 1/2 apart. Any tips? Also when I turn the engine over by hand I can hear some hissing noise coming from the bottom end b/c the oil pan is off. I don't think this is normal. Sorry for the novel, any ideas? Thanks!