I have both bottles but which to add today and which next time ???
Both less than worthless. No tests have ever shown any benefit to using them. Testing at NASA Lewis has shown that over time they can damage an engine because buildup of solid particles reduces oil flow.
None. Throw them out. Ever notice the only people who recommend additives are the people who make or sell them? No auto manufacturer, engine re-builder or parts maker recommends pouring goop into your engine. Don't do it!
