The point is, they have also given up some added engine protection buy going as thin as possible to make CAFE happy. Ford went back to 5W-30 from 5W-20 on the Coyote in 2021 ... and it wasn't for CAFE credits. It was to give those engines more wear protection, for the reasons I've mentioned in previous posts.
Euro oil spec thats better than dexos 1/r?
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But think about the oil squirters! Those poor pistons.
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I understand your point. However, do they or do they not still recommend a Ford spec?
The purpose of that example was to think about every aspect of an engine when evaluating for yourself whether you need to deviate from spec. HTHS, but what other properties are there of oil, and how does the engine interact with those properties.But think about the oil squirters! Those poor pistons.
Yeah, even Toyota has that blurb (shown many times here) in every one of their OMs that thicker oil will give more engine protection in more demanding use conditions. At least the Toyota engineers kind of try to get around CAFE in a round about way by making that statement in the OM. And how may OMs have been shown in this forum for the same engines used in different countries ... all showing a wide range of recommended oil viscosity. CAFE has made the engineers try to run as close to the ragged edge as possible, and they will ultimately sacrifice some engine wear for CAFE credits. When Ford designed the Coyote, during the test validation stage the engineers said it should have really been specified to use 5W-30, but CAFE won and it was speced to run 5W-20. Sure it "worked", but they finally woke up and did start specifying 5W-30 in the USA. It always was 5W-30 in Australia (no CAFE) for the Mustang.
The Ford spec defines the viscosity.
They go down to a 'dribble" when that 5W-50 is used in the Boss, GT500 and Coyote Track Pack.But think about the oil squirters! Those poor pistons.
Again, you resort to buckshot arguments. First it was “GM knows what oil its engines need” and now VAG. You’re ignoring the most powerful driver of corporate behaviors: government laws. CAFE fines automakers based on their fuel economy, which will artificially inflate a manufacturer’s vehicle price vs its competitors if it doesn’t meet the arbitrary standards set by government. So manufacturers find every way possible to avoid artificial disadvantages against its competition.
The easiest way to deliver miniscule individual increases which become somewhat noticeable over millions of vehicles is to use a thinner grade of oil. However, physics doesn’t care that people with no understanding of engines set unrealistic goals. Physics tells us that when HT/HS drops below 2.7 that wear skyrockets. This is why oil companies are developing new antiwear additives that can reduce metal-to-metal contact when MOFT cannot be maintained.
You can’t show a single engine whose lifespan has been shortened by going with an oil that has a higher operating HT/HS; conversely, there are countless examples of engines ruined by running oils with insufficient HT/HS.
Everything that I have that specifies a xW-20 automatically gets a xW-30, for all the reasons stated. Track use would get a xW-40. More film thickness is added wear protection headroom. Nothing negative about it except for maybe 0.1 MPG less ... but banging through the gears once per fuel fill-up pretty much negates that anyway.
All they're doing is selling you oil and you sending it back. Use it in a lawnmower if you'd like. Don't ask me how they make it work. I know they resell the used oil. Must mean there's a heck of a markup on oil. But yes, I do oil, oil filter, engine air filter, and cabin filter all through FCP.
Using Pirateship it cost me $18 to mail it back. I installed a drain plug with a hose on it and drain it every 5k miles. I don't truly believe it's bad at 5k miles and my UOAs have all shown it to be good it's just there's times where I get really busy and would forget.
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Why is it that I'm the one who keeps being tasked with providing information? When I provide the information it's never good enough, the goalposts change, or it's misinterpreted.
At least I can stay on track about things. Run the spec. That's what I'm saying the whole time.
On the other side of the debate it's pretty much gone from run the finest Euro oils in everything to it doesn't matter what oil you put in.
At least I can stay on track about things. Run the spec. That's what I'm saying the whole time.
On the other side of the debate it's pretty much gone from run the finest Euro oils in everything to it doesn't matter what oil you put in.
People that just "run the spec" viscosity don't want to understand Tribology and how oil viscosity matters by keeping moving parts separated, especially if the engine is pushed beyond normal somewhat benign street driving conditions. If it doesn't matter to them that's fine, not my machine. The specified oil works fine for the most part, but the level of engine wear protection may be lower than it could be. Specified oil viscosity in the USA is driven by CAFE, forcing the engineers to go as low as possible. But if there was no CAFE, you can bet they would be specifying thicker oil for the USA engines, as they do for the same engine used in other countries without CAFE requirements. Ford thumbed their nose at CAFE when they finally went up a grade on the Coyote. Probably saved them more money in warranty than using 5W-20 gave them in CAFE credits.
Pot, meet kettle. I've seen nothing to conflict with the general sentiment that is that you can run the finest Euro oils in everything. Everyone here is going to tell you to "run the spec" in warranty. Outside that, everyone is going to tell you to "run the spec" or better when the spec is not so demanding like dexos1.
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I haven't seen an explanation for why Euro is superior for all cases. All I've done is refute that.
This thread started because someone asked if they can get expect more from Euro oils than DexosR. Assuming he has a GM vehicle (why wouldn't he if he asks that type of question) the choices become:
Euro
https://www.mobil.com/en/lubricants/for-personal-vehicles/our-products/products/mobil-1-esp-x4-0w-40
DexosR
https://www.mobil.com/en/lubricants.../our-products/products/mobil-1-supercar-0w-40
Please, anyone, clearly describe why Euro is superior. Many experts here it seems. Shouldn't be a hard ask.
DexosR is Euro oil. Those two oils are very similar. The X4 is better though because it has slightly higher HTHS and holds its viscosity better in testing / UOA results. The program lead for that oil personally told me it was iterated on from the original ESP Formula which was renamed Supercar as part of the transition from Dexos2 to R. Those oils are so similar that we are talking differences at the margins. In fact, the X3 (nearly identical to X4) carried dexos2! It's a terrible question.
Euro (FS) is about half the cost for the same spec (dexosR). Seems pretty clear to me.
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Alright. What changed here?
Dexos2 got effectively split into R for gasoline engines and D for diesel in the last update. Corvette and Camaro oil was dexos2 and became R overnight. Manuals went from dexos2 to R in the next print.
From GM / Mobil page:
This has all been covered at length in many places.
Again, note that dexos2 was already Euro oil (it is based on ACEA C3). GM now states:
So, as you now see, since dexosR is a variant Euro spec off C3 just like BMW LL-04 or similar, and GM themselves say it is both superior and backward compatible with dexos1 G2/3, GM has answered your question and told you exactly what I said. Euro oil is better and even for a Cruze that specified dexos1 Gen 2.
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It's not something that I haven't seen. I picked those two oils as a comparison for a reason. I asked for further precision in your answer so that there was no ambiguity about it. They are equivalent.
DexosR isn't a less strict spec or an under-performing spec. Which Euro spec is better than dexosR? "Most of them." (+11 in agreement as of writing). No, no. Very few, actually.
It's like a knee-jerk reaction. Euro is better. Euro isn't even "Euro". There are categories within. We've been over 508 00 vs 504 00, and how 508 is even dyed green to make it apparent to use the right oil. Whereas dexosR "engine oils meet or exceed the performance of GM dexos 2 and GM dexos 1 Gen 2 and Gen 3 oils and are backward compatible," the same cannot be said for 508 00 with respect to previous revisions.
Mobil ESP X4 0w-40 has the approvals:
| Porsche C40 |
| VW 511 00 |
| Porsche A40 |
| MB-Approval 229.52 |
| MB-Approval 229.51 |
There's also:
"Mobil 1™ ESP X4 0W-40 can only be used in the vehicles for which it is approved. It is not backward compatible with vehicle engines requiring a C30 or C20. ***
Mobil 1™ ESP X4 0W-40 cannot be used in Porsche GT engines. There is a separate Mobil 1 product for GT engines, MOBIL 1™ C40 GT 0W-40.
You have to do your research when deviating from spec, if you can even call it deviating here for the engines that require dexosR. In this instance, you have enough information to make an informed decision. Certainly, it's possible to find advantages. It's also possible to do more harm than good, as evidenced by GM's specific LSPI tests (hence not all equivalent oils have the cert).
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So you’re saying you know more than the engineers that designed and tested the cvt?
Patman
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Apparently he knows more than all of us on here
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