So I have been using Mobil 1 5w-20 in my 2004 FORD F250 5.4l since I got it at 42k. It now has 130k. I was on the phone with Mobil and they told me that the Mobil 1 is not recommended for my truck as it does not meet the spec for it., Have I been doing damage to my engine all these years and what should I be using? I called them about using there Mobil 1 ATF in my 4R100 trans which they said meets spec and is fine to use.