Profile Topics Started Replies Created Engagements Favorites Search replies: Forum Replies Created Viewing 16 replies (of 16 total) ← 1 2 Author Replies August 4, 2013 at 9:47 pm in reply to: Oil Weight and Engine Performance #537607 Tom V.Participant My car, a 1990 Buick Century 3.3L V6, calls for 10W-30. If I use 0W-20 would that be a problem? My old mechanic, who I don’t go to anymore, said for me to protect the engine best, use 85W-150 gear oil. I said hell no and left. Author Replies Viewing 16 replies (of 16 total) ← 1 2