oil?

Does it have a CH-4 rating ?

I would very strongly recommend that you stay with dino oils until you have at least 10 or 12k miles. You need to give the engine a proper break in time and I have heard that the synth can hinder break in if used at first oil change (@3k). Using synth in a diesel is not really necessary but if you can afford 15 qts of synth then it will be easier on the turbo. I just use dino Shell Rotella 15w40 in mine (7.3l) changed every 5k miles religiously. So it is your choice but I would wait till after break in. As far as Mobil 1 you will need to make sure it specifically says it is ok for diesels and is approved by Ford or you may have warranty issues. Oils for gas engines do not have the proper amount of anti-foaming additives as well as not having the soot control ingredients. Jump over to the diesel stop and join the appropriate groups and they will be able to answer your questions in mind numbing details.

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