Sorry tabetha I completely disagree with you regarding the oil grade. 10w40 will cause the hydraulic tappets to not fill with oil as they should, or cause them to stick all together. Ford spend millions of pounds developing these engines to run specifically on 5w30 oil, and this is what the OP should be using, not 10w40, as what some bloke on the internet said. I do mean it in the nicest possible way!!