I'm loosing antifreeze out the overflow if i take my car on an hour drive or so, usually several quarts. It doesn't heat up, just pushing some out. The 430 engine is in great condition, car only has 45,000 miles on all original equipment. Head gasket maybe leaking or what should i be looking for? I don't see any white smoke at start up or any indication of those issues. \Any ideas will be greatly appreciated.