I got the oil changed in my car about a week ago, just prior to a rather long drive on a weekend trip. Everything seemed fine until I was going through some receipts today and noticed on the repair bill it said 10w-30 oil was put into the car. That seemed a bit off and when I checked, sure enough the manual states that the car should have 5w-30.
Kinda upset by this really... seems like they used cheaper stuff then they were supposed to. Is this an issue? I really don't know much of anything about engine oil, other than the 5w-30 should perform better in cold temperatures... and it definitely gets pretty cold around here.
Car is an 03 WRX, by the way.