Mobil 0w40 for my 7.3L ?

Indeed, the proof is in the pudding, which in this case is an arms-long list of manufacturer approvals for M1 0W-40 that the product has passed the requirements for.

Without actual tear-down testing, that's the data we have access to. Trying to use UOA's is like asking Ms. Cleo.
So the long list of approvals makes it a better oil? I am following you, and dont disagree, but 0w40 does not carry dexos rating, and the kirkland does so?????

I understand we are not talking gm, but we are also not talking mercedes either.

i dont disagree that 0w40 fs is not superior, fyi
 
It's not a new trend, it's actually a pretty old trend. Pushback was needed because people were trying to draw impossible conclusions from minute variances in PPM on UOA's; determining the "best" oil from these exercises, which simply isn't possible. That's why Doug Hillary took the time years ago to write the Used Oil Analysis article that's on the main page:
Exactly, and just like blackstone says, they don’t see any differences in wear numbers between oil brands. So Mobil 1 likely won’t be keeping his engine running longer for almost twice the price.
 
The OP literally said he gets Kirkland at $20/5 qt vs $37/5 qt for Mobil 1, both on sale. Huge price difference imo especially considering his sump needs two jugs
You and I clearly have very different ideas as to what constitutes a huge price difference. That's 22L of gas or likely about 1/6th of a tank for that truck.
 
You and I clearly have very different ideas as to what constitutes a huge price difference. That's 22L of gas or likely about 1/6th of a tank for that truck.
I don’t like to throw my money away just to calm my OCD/anxiety. That truck will run as long with either oil
 
So the long list of approvals makes it a better oil? I am following you, and dont disagree, but 0w40 does not carry dexos rating, and the kirkland does so?????

I understand we are not talking gm, but we are also not talking mercedes either.

i dont disagree that 0w40 fs is not superior, fyi
Yes, the long list of approvals make it a better oil. LL-01, A40...etc are more stringent in terms of testing requirements. This is why you see M1 0W-40 used at LeMans and Seabring in the 24hr cars and why GM had Mobil blend "Supercar" for them, instead of just using an OTS Dexos oil.
 
Exactly, and just like blackstone says, they don’t see any differences in wear numbers between oil brands. So Mobil 1 likely won’t be keeping his engine running longer for almost twice the price.
Yes, the tool lacks the ability to discern wear performance between different brands. That doesn't mean that if one were to perform teardown analysis there would be no difference in wear, varnish uptake, ring sticking...etc.

The problem is that it's the only tool people have access to, so of course they want to believe it can do all these things.
 
I don’t like to throw my money away just to calm my OCD/anxiety. That truck will run as long with either oil
This is Canada, stuff is expensive. A 1-ton truck that doesn't get worked and spends half its life idling is the definition of throwing money away, in that context, getting worked up about $34 is asinine.
 
Exactly, and just like blackstone says, they don’t see any differences in wear numbers between oil brands. So Mobil 1 likely won’t be keeping his engine running longer for almost twice the price.

Yes, the long list of approvals make it a better oil. LL-01, A40...etc are more stringent in terms of testing requirements. This is why you see M1 0W-40 used at LeMans and Seabring in the 24hr cars and why GM had Mobil blend "Supercar" for them, instead of just using an OTS Dexos oil.
is the latest 0w40fs the same thing as supercar?
 
With his style of use and sump size it may be overkill to pay almost double what he’s paying for with Kirkland. The recommended oil by ford is a syn blend so a group III oil like Kirkland is already better than what the mfg recommends.

I don’t agree that a spectrographic analysis is useless in his case. He can see how wear numbers compare between the two oils during a snapshot of time
Okay sure. But the question was whether the Mobil 1 0W-40 was a better oil, which it is.

And a UOA cannot be used like this to perform comparative analysis between oils. There are far too many uncontrolled variables. The ASTM method for comparative wear analysis is complicated and expensive, as it needs to be in order to isolate the relatively tiny variable of the oil.
 
Exactly, and just like blackstone says, they don’t see any differences in wear numbers between oil brands. So Mobil 1 likely won’t be keeping his engine running longer for almost twice the price.
So this is the answer to whether a UOA is useful here for wear comparison. It isn’t.

But wear control isn’t the only attribute of motor oil. Oxidation resistance, resistance to deposit formation, coking, ring sticking, all these are more important than wear IMO. The Mobil 1 product is superior in that regard.
 
With his style of use and sump size it may be overkill to pay almost double what he’s paying for with Kirkland. The recommended oil by ford is a syn blend so a group III oil like Kirkland is already better than what the mfg recommends.

I don’t agree that a spectrographic analysis is useless in his case. He can see how wear numbers compare between the two oils during a snapshot of time
He didn’t ask, “will both of these oils be sufficient for …”, he asked is M1 0w40 a better oil, not is the M1 overkill compared to the Kirkland for “xxx use”. And in every single regard, the answer is yes. The Kirkland may meet dexos1 requirements, but that is essentially just paper requirements. The M1 FS 0w40 carries several Euro mfr certifications, which include several engine & use tests. Those will always be more informative than mere characteristics.

Also, spectrographic analyses DO NOT compare wear metals. They merely give a count and not a qualitative analysis, nor an indication of where said elements came from. Different oil chemistries can simply liberate accumulations, which in your claim, would lead one to believe wear was worse.

There’s lots of good indication this is where M1’s “infamous” “moar iron wear!” claim from poorly educated people misusing UOA data originates from. And there’s zero actual data to back that claim up.
 
Kinda wanted to in my 2017 Honda Accord Sport 2.4 with almost 400,000 miles but kinda waiting for someone to give me a indication thats okay in gdi engine and such.
Send it. Lots of folks using it in GDI engines with no issues. If you're talking about possible increased IVD using it in GDI, that has way more to do with the engine's oil vapor management, valve stem seal condition and the state of other mechanical components than just the mere use of a full SAPS oil like the M1.
 
That 7.3L gas motor would be expensive to replace. I don't get the concern over the cost difference of an oil change that happens only occasionally.

It sounds like @JWC86 has maintained the engine to a high standard. OP has used Kirkland 5W-30 since new and suggests the motor is happy. Is there any reason to switch brands after 100K worth of happy miles?

Although I think Mobil is "better" (Castrol is my brand), the fact is Kirkland (whatever it is) seems to have served you well....why change? Costco has their own reputation to protect. Kirkland oils may or may not have the highest approval ratings, but they have approvals for things like Dexos and API. That's something.

Scott
 
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M1, this grade, is one of the best off the shelf oils money can buy.

For your truck, it’ll be great. It has higher amounts of additives and the key here is that it has a HTHS of 3.5 -3.7, whereas the Kirkland is 3.0-3.2.

Also M1 has MB 229.5, Porsche A40 and BMW LL-01 ratings. All crazy hard to meet (especially the first two).
 
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