Hello. Got rid of the Mercury Mystique "problem" yesterday. Bye-bye! Now -I- am visiting my family members up in Madison, WI. Noticed my aunt has a 2002 Ford Focus that she describes as a piece of . Naturally, i asked about the oil and its been "going on 8000 miles" as she said, and she does not remember what oil it was. its starting to get cold here, too. Of course i offered to change the oil and aside from a transmission that doesnt always catch when driving the engine sounded ok. In two weeks or so i can change her oil. I have not popped the hood yet. Getting chilly up here, big change from Dallas. Brrr. Should i check out an 0W-30 like Mobil 1 from Walmart, or go 0W-20 in this car? I did NOT catch the mileage of this vehicle, but the engine sounded good and felt strong, aside from the transmision. Is 0W-30 synthetic a better choice over 5W-20? My biggest issue is the 5 number.. should it be? ..Supertech 5W-20? This may be an XOM ST area. Even if it is not, please help me select an oil. I am not used to these 4-cylinder Fords. Thank you.