Which Mobil oil for my 7.3

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Nov 1, 2007
Messages
6
Location
mississippi
I have been using Mobil delvac 1300 super 15w40 in my 1997 F250 7.3 since I purchased in new. Now has 270,000 on the clock. Change every 4000-5000 miles. No problems at all! To my surprise. Ford doesn't recommend it. Mobil doesn't recommend it in Turbo diesels. I want to stick to Mobil, but which one? The 2 obvious choices are Mobil 1 15w40 extreme synthetic or Mobil 1 5w40 turbo diesel truck synthetic. I might like the 5w for starting ease in winter. But wouldn't want to swap to something else for summer. Any thoughts?
 
Ford doesn't recommend Mobil oil for their 6.7. 15W-40 is good to below freezing.
 
Where does Ford state that they don't recommend Mobil oil?

There was a recommended list posted about a year or three ago with Fords oil recommendations for the 6.7 engine. the list on on the web do a search.
 
There was a recommended list posted about a year or so with Fords oil recommendations for the 6.7 engine. link to list
That link doesn't work. While I don't think you are lying, I find it hard to believe that a manufacturer would list a specific brand to avoid. Meeting a spec or not is different than Ford actually stating that they don't recommend the oil.
 
Where does Ford state that they don't recommend Mobil oil?
Go to the Mobil website. Entered my truck. 97 F250 7.3. Came back with the Ford spec number. Said we have no oil that is offered in North America that meets this requirement. This can be verified in my forms. Where Mobil oil and power stroke diesels are mentioned
 
That link doesn't work. While I don't think you are lying, I find it hard to believe that a manufacturer would list a specific brand to avoid. Meeting a spec or not is different than Ford actually stating that they don't recommend the oil.
Here is a working link to oils that ford says are approved. https://www.fcsdchemicalsandlubricants.com/additionalinfo/dieseloilsWSSM2C171F1.pdf
Mobil delvac 1300 doesn't meet the standard which i think is due to it being SN as well. I think 800 phosphorus is SN standard? with 1200? phosphorus being standard for the ford spec.

Heres their official statement too which goes back the the 7.3
 
Where does it say not to be used with a turbo?
At Mobils web site. They break down the
Where does it say not to be used with a turbo?
This was copied and pasted from Mobils web site. In their description for Mobil delvac 1300 super 15w40 This seem to indicate it's NOT for use in turbocharged diesels
  • Diesel applications using older and naturally aspirated conventional designs
 
Here is a working link to oils that ford says are approved. https://www.fcsdchemicalsandlubricants.com/additionalinfo/dieseloilsWSSM2C171F1.pdf
Mobil delvac 1300 doesn't meet the standard which i think is due to it being SN as well. I think 800 is SN standard? with 1200? being standard for the ford spec.
I saw that too. So knowing this. What should I do? I think I should at least stay with Mobil. Since I've only used Mobil delvac 1300 for 270,000 miles. Mobil 1 5w40 turbo diesel truck seems to fit for the 7.3 although not specifically recommend by ford?
 
Delvac Super is factory fill in the DMax
This was copied and pasted from Mobils website. Under products description. This is under Mobil delvac 1300 super 15w40 If it was recommended for turbo's, They wouldn't have said this!
  • Diesel applications using older and naturally aspirated conventional designs
 
They don’t recommend the oil because it doesn’t mean their specifications, not simply because it’s Mobil.

If you want to use Mobil 1 then TDT isn’t a bad choice.
Yes, I also see on forms. Several people using it in their 7.3. one even knew of this "not recommended problem" said his truck loves it. Would never change! I believe that is what I will try. Thanks for your suggestion
 
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