[egiap's 5.0]

Your car should take 5w30 or 10w30. The 15w40 should be fine in your car. Never mix two different weight oils. Most car makers require the use of lower weight oils to bring up fuel mileage to goverment specs. Keep a eye on oil level since your changing brands. The different detergents in oil might work at any varnish around seals and cause some oil consumption. Hope I helped.