Is anyone running Amsoil 5W-50 in their FGT?

[GTMikey]

Has anyone switched from Motocraft to the new Amsoil 5w-50 and posted any analysis numbers on this? Just curious.

 

[GT Tech]

Some years ago, while dyno testing a prototype Ford Racing crate motor at Roush's dyno lab, we ran back to back comparison pulls between Mobile 1 and Amsoil. The Amsoil pull was within 1 HP of the Mobile 1 pull. A statistical dead heat. We didn't try the Motorcraft (Conoco-Phillips) full synthetic, but I would think it's in the same neighborhood.

 

[Biginch Blake]

Is there a shortage of Motocraft 5w-50w oil? I run it in all my cars and have had good luck, why smack the Hornets nest. Ford oil works!

 

[jcthorne]

Actually, used oil analysis has shown the Motorcraft breaks down long before normal oil change interval is over. By 3000 miles its MUCH thinner than spec. I will no longer use it.

 

[Indy GT]

Counterbalancing the above, I change the Motorcraft oil in my GT MUCH sooner than 3000 miles, thus the "thinner than spec" observation is a moot point.

I will continue to use the recommended Motorcraft oil in my 5.4. (But I did convert to Rotella, per your data, in my other daily driver).

 

[06fordgt]

I have not yet but do run it in my Shelby cobra 427 stroker motor. Since its is way past warranty might be a good idea to change it over now.