I've noticed that many people are using mobil 1 5w-30, instead of the recommended 5w-20 from ford. Why did you switch? How does it affect horsepower, engine durability etc. What is the difference between 5w-30 and 5w-20?
I'm using Mobil 1 0w-30, better than 5w-20 at both extremes. the 0 viscosity is thinner when its really cold, so better oil flow during cold starts. The 30 viscosity is thicker when its hot so more oil film when its hot. At least that's my theory...
I use it because it is better than conventional oil and the service manager at the dealer I bought my car told me that it is fine that I use that oil and that the 5w20 is too thin for these cars. (if you want it to last a long long time) matter of fact after I had the tick fixed he told me to change it to a thicker oil as soon as possible.