I have heard this too. Actually, I have been told by a few knowledgable sources that some Mopar engines should be run a quart or 1/2 qt low....can't remember why but I think it has to do with the oil windage. Maybe this is more for race cars? In my 340 I run a deep Moroso pan and was told to not fill it to the line, there is plenty of oil in the engine and the sump is deep and has plenty of oil to suck up.