Don't know anything about the 3.6 but the 3.8 that I have is a super engine, ton of miles, and has not given me any trouble in any of the cars I had with one. GM did reduce their oil service life indicators for the 4 cylinder because timing chains were snapping. Probably more of a bad engine design, than an oil longevity issue. Anyway, it was just an article of interest and whomever reads it can follow it or not.