I think I shamed my dealer at my 1st oil change. I took in 6 quarts of 0-W30 and also the filter after they told me they just used the semi-synthetic over the phone. Told them to use what I put on the passenger seat (no way that tech could say that he didn't see the parts in the back hatch). AS IF BY MAGIC, they happened to find the 0-W30 oil and didn't touch my oil or filter. I just smiled and drank their really nice latte's out of the fancy machine!