There is one thing that I've never understood or been able to rationalize. I've always heard that synth is soooo good it's not a good idea in a brand new engine because the engine needs to be broken in (valves, rings etc). OK let's presume this to be the case... How does this allow for those engines that come from teh factory brand new w/ synth oil (e.g. the infamouse Corvette example among others)??? I've never been able to put those two scenarios together. Any help here...? --- BTW if you ever visit the Vette factory in TN - just watch how they run the snot out of those cars right on the dino as they come off the line and then down a small test track 'course' and to the loading lot - WOT all the way! Break-in period indeed!