Break in oil?

[Randy B]

I could go on, but suffice to say it's no myth.

"Years ago" oil had MUCH higher levels of [url=http://en.wikipedia.org/wiki/Zinc_dithiophosphate]ZDDP than it does now due to tighter emissions regulations. With the proliferation of roller valve trains the need for it has been reduced and this had allowed the government to pass more stringent regulations in regards to ZDDP and thus "break in oil" was born. It is ONLY to be used for short periods to break in an engine, not full oil change intervals UNLESS the engine is of a flat tappet design with no catalyst. ZDDP destroys the catalyst in a much shorter time frame than it would normally wear out.