I recently changed my oil (at the 6k mark). I am using Valvoline DuraBlend 10W-30, since it's summer. Anyways, when I checked the previous oil level, it was low! Does the RS burn oil or something? It wasn't leaking; I checked for that. So I was thinking of putting 5 quarts in instead of 4.2. I didn't, though, because it could be really bad, so I thought I'd ask you guys (and gals) for advice for the next oil change.