Man I am so angry! Last week I had my car in for a heater fix, and during that time they noticed my oil filter was a bit loose so they tightened it up. I am now pretty sure that they topped up the oil as well, so they have effectively now ruined my first oil interval with Schaeffer oil! I am 2.5k into a planned 5k interval, but now I don't think there is much point having this interval analyzed, since it's now tainted with probably a half a quart of their crappy bulk 5w30 oil most likely. I'm going to put a call in to the service advisor to confirm, but I am pretty sure this is what happened, since my oil level is now mysteriously a half quart higher (I was letting it get low since when my dipstick reads full it's actually a half quart over) I doubt I'm getting any contamination into the oil that would cause this level to rise, and mysteriously the oil is a bit cleaner too (which would indicate it's been topped up) So now I can't figure out what to do. Should I finish off the interval and analyze it (even though it's not a true sample) Should I change it out now and start over? Should I keep it in there to the full planned 5k, but not bother to analyze it? ARGGHHHH!!!!