Maybe someone can answer this for me. Could I use M1 0W-40 in my '02 Toyota 4runner? I have heard it is really a high end 30wt, is this true? And if so, would it be something that could be used in a toyota engine? I'm also trying to get the best gas mileage as well and since I can't find GC 0W-30 here I thought maybe M1 0W-40 would be a better option. Any input?