[olrocker]

You know, with modern cars, you do not - and you really SHOULD not - use ANY oil, engine, or fuel additives. First off most of that stuff is snake oil, and secondly the stuff that does work is really designed for older engines with lower machining tolerances and generally less precision. Some of that stiff could actually hurt your engine.

So long as you use top tier fuel from the likes of Sunoco, only use 91+ octane, and change your oil regularly (5,000 miles or less) with ONLY Mobil 1 0w-40 green label ESP or Supercar, and flush your coolant and use only the GM Dexcool every 50,000 miles, your engine will run reliably and with every pony it was born with for 200,000+ miles.