Aside from all the already known good oils....nothing comes to mind. Valvoline Premium Extreme, Rot T6, MC 5w40 would be great choices.

Since the new 6.7L doesn't need oil for the injectors it's not too hard to pick an oil.

 

You're gonna get so many answers lol... Stick with big name brands most of the time and you're going to be fine. I have personally used Delo and Rotella on all the diesels industrial equipment, commercial trucks and my own just fine. As long as its diesel rated you're fine. I have no beef with any company except Amsoil... They are a good oil but not the magic that makes the world go round for the price they charge lol. But hey its not my wallet either.

Rotella, Delo, Motorcraft, Valvoline, Supertech, Castrol, are what I use on a day to day basis with supertech being for projects and super old vehicles that just get worked lightly, lawnmowers and that type of stuff etc. Most never change oil in snowblowers, lawnmowers anyways from my conversation with other owners lol.

 

Rotella T6 user here. I buy it when it’s on sale for $135 for a 5 gallon bucket and then get a $35 mail in rebate that I apply online for from Shell.

 

@Heavy_GD , you think the oil in post 5 is OK to run in the 6.7?

 

Its the perfect additive to run between the seat and the steering wheel.

 

Any oil on this list in the proper weight for your use.
10w30 if no bio laced fuels and not towing.
5w40 for towing, bio, and cold temps.
15w40 for towing, bio, and moderate temps.
Sorry to say, Valvoline Premium Blue is not on the list.
Motorcraft synthetic is way overpriced for the quality in the bottle, seek out Kendall or Phillips66 for the identical oil to MC plus a titanium additive,

https://parts.ford.com/content/dam/ford-parts/resources/motorcraftpdf/Diesel_Motor_Oils_Meeting_Ford_WSSM2c171F1.pdf

 

Sorry to say, Valvoline Premium Blue is not on the list.

https://parts.ford.com/content/dam/ford-parts/resources/motorcraftpdf/Diesel_Motor_Oils_Meeting_Ford_WSSM2c171F1.pdf

 

Well @BigGreen06 you started this... whats the best oil?

 

Not a subjective question at all! I tried them all, even the unrefined stuff! Now it’s vegetable oil only. Really takes the noise out of the muffler bearings

 

"Would the Valvoline 10w30 and 15w40 Heavy Duty on the list not be a Premium Blue? "
Valvoline Heavy Duty is not Premium Blue. It's an entry level oil that comes in a white bottle like their Daily Protection for cars. It was a flash in the pan, here then gone in about a year.

 

I used it in my 6.0, my 6.4, and my 14 6.7, and it seemed to be great for them. I've been using the Ford stuff and its been fine, but I think I can get oil cheaper on my own, than what the dealer charges.