Best synthetic oil for 2017 Ford F250 6.7L Diesel

[Agamarne]

Also 5w40 vs 15w40 opinions. I realize this topic has probably been covered many times, but I want the latest and greatest opinions and minds to base my decision off of. Also does anyone know what the Factory Fill might be on this truck and oils - https://carwrenching.com/best-oils-for-6-7-powerstroke/ Why is Amsoil not on Fords approved oil list? I tow 8500lbs-9000lbs 5-6 times a year. temperature here is 32-105 degrees. June through September are typically over 90 degrees.

Edited March 2, 2020 by Agamarne

[Black02Silverado]

Welcome to GMT.

 

As for oil, according to Ford the recommended oil is a 10w-30 diesel oil for normal use and for severe use 5w-40.  As for factory fill I don't know.  Also the reason AMSOIL isn't on the Ford list is because they did not pay to be on that list.  It doesn't mean the oil doesn't meet specification. Just that if you want the manufacture to approve your oil you have to pay them.  This is also why AMSOIL isn't on the GM dexos list.

 

With newer engines and quality oils 15w-40 isn't really needed.  If it was then Ford would recommend it and nothing else.

 

Since you tow some and have a warm summer I would go with what Ford recommends and that is the 5w-40.  AMSOIL's  Signature Series Max-Duty Synthetic diesel oil would work great along with the EaO98 oil filter.

 

I would also suggest you change out your differentials and transmission fluid.  Those take a beating when you tow and having a quality synthetic really helps extend the life of those components.

 

If you are interested in a quote, PM me your address and what you might be interested in and I can get one out to you delivered to your door.

Edited January 31, 2020 by Black02Silverado

[diyer2]

This will work.

https://www.walmart.com/ip/Shell-Rotella-T6-5W-40-Full-Synthetic-Heavy-Duty-Diesel-Engine-Oil-1-gal/102646780

This

https://www.walmart.com/ip/Mobil-1-5W-40-Turbo-Diesel-Truck-Motor-Oil-1-gal/17128879

This

https://www.walmart.com/ip/Chevron-Delo-400-XSP-Synthetic-5W40-Motor-Oil-1-gal/20896087

 

[txab]

Buddy of mine is running the T6 5w-40 Rotella in his Ford. Get's great UOAs. He is constantly pulling a gooseneck loaded down with round hay bales

[Grumpy Bear]

Ford "approves" the API service class FA-4 and does not approve the CK-4 class. How is that classification different? It differs by which SAE viscosity grades are approved. 5-10W30 and 5W40 are approved. All others are not. All FA-4 oils ARE CK-4's. Other than that, the FA-4 and CK-4 classifications are identical. You can choose to run a CK-4 in a motor specified for a FA-4 BUT you CANNOT run a FA-4 in a motor not designed for it. There are engineering elements in metals, their heat treats and surface finishes and coatings that allow the use of the less vicious oils. The driver of course is fuel efficiency.  

 

Some issues with the FA-4 oils. They rely HEAVILY on anti-wear additives to do the job film thickness should be doing. (Film thickness is proportional to viscosity for the same fluid gravity and elemental chemistry). Oddly the newer service classes (since CJ/SM) lowered the levels of phosphorus and zinc, (ZDDP) the primary anti-wear additives and replacing them with others such as titanium, boron and moly which are more anti friction than anti-wear. Lower viscosity, lower anti-wear additives….squeezing the safety factor right out of the oil. Fleet Owners are strongly cautioned to employ UOA, not for wear, but for fuel dilution to prevent stepping off the viscosity protection cliff. Additives cannot replace another function of oil. Cooling! Especially under high load situations.

 

And what is all this worth in terms of fuel savings?

According to Lubrizol?

0.7% - 2% in Fleet Use for OTR's. 

 

Lubrizol (and Chevron) bench test fuel efficiency results compare oils of the same base oil types for the hype of these fuel savings. That is a Group III/PAO 5W30 to a Group III/PAO 15W40. Things get a bit more complicated when we change the base oil to a PAO/POE blend with the same additives. This blend is one of a polar and a non-polar fluid which is a good deal more "slippery" than the former. (Lubricity) Enough so that the latter consumes no more energy, although more viscous, than the former. (once up to operating temperature). 

 

In addition there is enough difference between the densities of a Group III and a POE that, when the proportion of POE is high enough, over 20%, (and it is) the film thickness of the POE blend is about one viscosity grade higher. (Providing the *W* spread is reasonable) That is, it would be more true of a 15W40, 25 points and less so of a 5W40, 35 points. Difference in polymeric thickener volumes. Fact is most high POE content fluids have enough VI to drastically limit or even dismiss such additives. A 5W20 POE blend has none for example, 15 points.

 

Logic point. The fact the motor has to be 'designed' to run a FA-4 to be reliable is a warning. 

 

Two oils that fall into that camp are AMSOIL Diesel and Red Line HP Diesel 15W40. In fact if you plug in your vehicle into the Red Line site it will suggest this product. 

 

Now, having said ALL of this there isn't a single oil that has been suggested that isn't up to the task although I personally am not a bit fan of Mobil. Those are the facts as I know them. 

 

Now for my opinion:

 

Not my truck, I don't care but ask yourself what you are protecting?

Your driveline? Your oil? Your wallet? 

Then ask how much is enough.

 

If you choose the Group III/PAO blends then 5W40, not *w30 and still watch of fuel dilution. Rotella, Delo are both solid choices but anything that carries the FA-4 symbol is okay. Don't skimp on filtration. 

 

If you choose a PAO/POE then AMSOIL SS Max Duty Synthetic 5W40 or Red Line HP 15W40. And STILL don't get carried away with OCI distances. Don't skimp on filtration. 

 

 

 

 

 

[L86 All Terrain]

I buy Rotella T6 for my fleet of diesel engines, mainly because it goes on sale for "off brand" prices at Canadian Tire. If it were a personal truck I would consider Amsoil Maxx Duty or Royal Purple but Rotella is good stuff. 0w-40 winter, 15w-40 summer is what I do (-30c winter, +30c summer). Have got over 1 million km, 20,000-24,000 hours on most of our truck engines historically, even a Cummins ISX believe it or not.