The lack of true 85% ethanol and inconsistent batches drove me away from pump E85. Now I make my own cocktail blending E98 with 87 non-E (plus a few choice additives
).
Is Mobil 1 0w-40 too thin?
- Thread starter John9721
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The lack of true 85% ethanol and inconsistent batches drove me away from pump E85. Now I make my own cocktail blending E98 with 87 non-E (plus a few choice additives
).For the purposes of oil selection, not really. Friction/wear peaks around E50, which is generally below the mandatory minimum for pump E85.
The main problem with pump ethanol is the quality of the gasoline used as the basis for the mixture, as well as potential water contamination from less trafficked pumps.
Any of the cheap 40-grade Euro you find at Walmart will work fine for you. As @kschachn said above, they're 40-grade, Facebook lore notwithstanding.
Are you using a true E85 tune or more of a mix like E30? And do you have an ethanol gauge on the fuel like Fuel-It? When I had my GTI with a custom E30 EQT tune on a stock IS20, but Autotech HPFP, I had to be very cautious that I had an exact percentage, otherwise my fuel headroom would take a dump. Most consistent station for E85 was anywhere between 60-80%, so I would fill and mix then check with Fuel-It to make sure it was right at E30. Mix in more E85 or 93 if not. Would not risk going full E85 tune because of the inconsistency, not to mention higher added cost for fuel delivery upgrades.
Always used Castrol 0W-40 and never had any trouble with it being "too thin" on any UOA, even with the horrible fuel dilution I was getting (~3%). Can't imagine M1 0W-40 would be much different, but UOA for certainty. If you're having issue with fuel related thinning, and you don't have leaky injectors or they are not running wide open windows, consider something along the lines of the HPL like @RDY4WAR suggested.
Perhaps you missed the part about concern on oil dilution. It makes the scenario more logical. Still, I am always in favor of staying with manufacturer recommendations.
It would take forever to get that oil up to temperature and once it got there, it would be tough to get it to go away. A balance needs to be found through application. I wouldn't race on 99.9% 0w20 oils and wouldn't drive two blocks on 10w60 to get more Budweiser 0.0 NA beer.
Patman
Staff member
The nice thing about ESP 0w-30 and 5w-30 is that they have pretty much the same HTHS as the 0w-40 anyway.FYI
M1 FS 0W-40 passed the torch to M1 ESP 0/5W-30.
Did you miss the memo?
Although having the Porsche A40 approval on the 0w-40 is definitely something to consider if you need that little bit extra protection (especially for a track driven car)
Thus the move to 40 grade. Perhaps you missed that part. Then again the motor is tune only. I guess that tune allows more fuel past the rings...
https://upload.wikimedia.org/wikipedia/commons/6/63/Vapor_ethanol_mixtures_Fig_4.3.jpg
It would take longer to get up to temperature? I didn't recall grade being a measure of specific heat.
What is the point you are making with the ethanol v vapor pressure chart??? Need to buy a vowel here…
The physics behind the situation indicate the "prehaps you missed' intro was unnecessary, being that ethanol blends are inherently more likely to clear from the crankcase.
It's pretty common these days to install a flex fuel sensor so you don't need to carry out a science experiment at the pump anymore. It reads the E% and ECU accounts for it
We're on M1 ESP X4 0w40 now, got that 3.8 HTHS, <3% shear, and Autozone bundle discount.FYI
M1 FS 0W-40 passed the torch to M1 ESP 0/5W-30.
Did you miss the memo?
Did not mean to offend. I am not sure that I have heard this before. You are suggesting that fuel dilution is lessened by using the right ethanol blend? You are saying that the blend’s vapor pressure is the critical variable. It sounds plausible…. But a new theory to me
Great, Thank you!
looks like I missed the latest memo.
I am way behind myself. Still on M1 EP 10W-30.
One of the jobs of crankcase ventilation is to clear the lube oil of fuel that gets past the rings. Even on modern diesels (higher vapor pressure fuel) that use post injection for DPF burns, time at temperature is sufficient to keep dilution in bounds as long as the engine is given the opportunity to operate at temperature.
So not only is the move from 20w to 40w a hedge against dilution, the move to ethanol blends (lower VP) enhances the mechanism by which the fuel ultimately gets cleared from the lube oil, countering dilution.
That said, ethanol has other detrimental chemical impacts on lube oil, for which the 40w seems to be an accepted band-aid.
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So true. I used to opt for 5w30 m1 esp on my track car over 0w30 thinking it should have less VI and better shear/heat resistance. Apparently it does not work that way.
I know quite a few people whose car calls for 0w20 in the usa (and 5w30 in Australia), and they run M1 euro 0w40 on track with flex fuel. I don't run e85, so I have never paid enough attention on UOA with e85 tuned cars to see how much of dilution we are talking about it here. But since i presume these folks would have research through it already, so I would expect m1 to work just fine
Castrol Euro 5w40 held up longer than m1 0w40 in the Audi 3.0t sc. The 1.4tsi took 5w40 as well. The 2.0t looks to fit right in the middle of the VW line up lol, you see a pattern here? The 5w40 will do well to absorb the turbo heat, viscosity is king, just change it every 4-5k. Oil pressure should be better too.
Also, I could have swore there was an article about how vw504 oil, which is very good oil, does not do well with ethanol. With Europe not mixing ethanol in their gasoline/petrol like we do. Anyone else confirm or deny? But right now the jetta has valvoline xl-iii euro 5w30 in the 1.4tsi, it's vw504 and came with 2 car washes at the express lube. Will have an oil analysis in a few months, 250,000km coming up.
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Anything with a Porsche A40, or MB 229.5, approval is going to be fine - it’s not “too thin” if it has those approvals. What matters is HTHS, not a change of 1 or 2 CsT. So, do you want a thick 30, or a thin 40 - frankly, it doesn’t matter.
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