Why wouldn’t you just buy the 5W-30 ESP off the shelf? Are you starting your engine below about -30?
FA24DIT Oil recommendations
- Thread starter JJay03
- Start date
This is just what I am thinking so not saying its correct. The Valvoline EP cSt at 100c is 8.8, the 5w30 Pennzoil UP is 10.3 and the M1 ESP 0w30 is 12. Someone that drives a lot of highway miles in the WRX group said they actually lost 4mpg on the M1 ESP 0w30 over the 5w30 they were using. Makes me wonder if I need to go that thick or the PUP will be a nice in between from what I was using with the Valvoline 0w20 to the M1. I wont be driving a lot of highway miles but that seems to be a lot of efficiency lost and a big jump in viscosity from the 0w20.
No way they lost 4mpg from an oil within the same grade. Apart from the fact that no one could ever come to that conclusion based on an observation of everyday driving. Such a change is deep in the noise between grades, much less within one.
They guy has no idea what he’s talking about and is also completely unaware of what he’s up against in making that claim.
He said he commutes on the same route everyday and drives to get the best MPG. I cant verify of course but also still wondering if I need to make that big of a viscosity jump from the 0w20 I was using.
That makes no real difference. The variables are there and are much larger than the oil.
An oil with a higher HT/HS is always beneficial in terms of wear and mitigating fuel dilution. The downside of a tiny increase in fuel consumption is unmeasurable in everyday driving.
Here is someone who knows more about it than I do. He’s discussing different gasoline, but the principle is the same. Many people observe things and then ascribe that observation to an unwarranted and unproven variable, especially in a chaotic system like this. They fundamentally do not know what they are doing.
Either way, a 4mpg difference within the same grade is ridiculous at the core.
The graph below represents several years of my actual MPG that I calculated on each fill-up. Same driver, same car, same oil brand and grade, and mostly same gas station. The spikes up and down are from long freeway trips or traffic jams, but most of the data falls between the red lines, which is +- 14% from the average, a 28% range! Trying to attribute a couple of percent move (i.e. 0.5 mpg) to changing one variable is not possible from such point scatter.
And here are a few of the variables that can affect fuel economy:
And here are a few of the variables that can affect fuel economy:
- Tire pressure
- Tire...
Not sure I buy that a higher HTHS is always beneficial. Up to a certain point im sure depending on the engine and its tolerances. I do agree that 4mpg seems excessive just for oil but who knows. Ive had 4mpg swings on mpg with seemingly the same conditions but I dont drive the same exact route for work every day on the highway like I use to. I am not an oil expert either so I just try to learn through others who might be lol.
Always for wear. And it always helps with fuel dilution. Tolerances? What do tolerances have to do with it?
Formulators and manufacturers have stated that there is approximately a 1 to 2% improvement in a grade change. If you normally achieve 25 miles per gallon, that is a maximum difference of 0.5 MPG. And this is a change in grade.
Did you look at that list TomNJ posted? Many of those variables he lists are highly significant. For example as he notes, gasoline itself varies in BTU content, even at the same gas station it can vary about 4% - and this is independent on seasonal blend variations which are also very significant.
No one, ever, driving in the real world will observe a fuel consumption variation that can be attributed to the single variable of the oil. Seeing something is the easy part. Ascribing it to one or more variables is the much harder part.
Last edited:
Again, Im not an expert but then maybe google is not either?
Engine Tolerances and HTHS:
Modern engines, particularly those with tight tolerances like modern LS and LT variants, are designed to utilize thinner oils with lower HTHS values. This is because tighter tolerances allow for lower viscosity oils to maintain adequate lubrication, contributing to improved fuel efficiency
Basically a balance between fuel economy and wear protection right? I am trying to find that middle ground. If I end up using PUP and my UOA's dont show adequate protection then I will try something else. My oil will be changed by time around 6 months before it gets close to any of the mileage limits.
If your saying forget fuel economy then get the highest HTHS for the specific grade? If so then I am not disagreeing because fuel economy is not that big of a deal for the wrx really but I want decent mileage in the Outback.
Neither car will be raced or abused. I dont drive as hard as I use to but will have those spirited drives on a nice day like mentioned.
Engine Tolerances and HTHS:
Modern engines, particularly those with tight tolerances like modern LS and LT variants, are designed to utilize thinner oils with lower HTHS values. This is because tighter tolerances allow for lower viscosity oils to maintain adequate lubrication, contributing to improved fuel efficiency
Basically a balance between fuel economy and wear protection right? I am trying to find that middle ground. If I end up using PUP and my UOA's dont show adequate protection then I will try something else. My oil will be changed by time around 6 months before it gets close to any of the mileage limits.
If your saying forget fuel economy then get the highest HTHS for the specific grade? If so then I am not disagreeing because fuel economy is not that big of a deal for the wrx really but I want decent mileage in the Outback.
Neither car will be raced or abused. I dont drive as hard as I use to but will have those spirited drives on a nice day like mentioned.
Last edited:
Patman
Staff member
Even Google is getting it wrong. It should substitute the word clearances where it’s saying tolerances. It’s a common mistake that many people make when discussing engines.
That’s not correct.
As Patman noted above it should be clearances. But even then that’s not what changes as engines are designed to tolerate thinner oils, it’s the bearing width.
Beyond that, these changes allow an engine to tolerate the decreased HT/HS without excessive wear. They don’t preclude the use of a higher one.
You’ll be better served by ensuing the engine is in proper mechanical condition and that the tires are properly inflated.
Maybe I will try the M1 ESP in one and the PUP in the other. If one seems to run smoother with less engine noise I will choose that one. I could also just continue to run them and get UOA's for both for multiple changes and see how they do.
Reminds me of 2006-2008 or so when everyone liked the 0W30 German Castrol for the LS1. I tried it in my 01 SS Camaro but the piston slap was terrible with that oil for some reason. Went with another synthetic 5w30 and it was quiet.
Last edited:
Who said the ESP was too thick for clearances?
Glenda is Roki still making the OEM subie filters?
I'm trying to find some sort of current production Roki filter and I'm pretty sure most Subies are M20s with the honda-compatible gasket ID,
Yes. You can still get them. Some use Mazda Tokyo Roki filters on Subarus. I cut this one open recently. Great build quality but no published efficiency that I can find.
Off a friends 2024 Crosstrek. First oil change at 1000 miles. No idea what he put in and on. Very high quality filter IMO. Only gripe would be I prefer a coil spring. Filter reeked of gas.
Piston slap is not caused by, nor cured by oil choice.
Not saying the oil caused it as it was a known issue with many LS1's back then partly because of the short skirts on the pistons. A different oil made it quiet enough to where I did not notice it.
Here is a post about it from 07. https://bobistheoilguy.com/forums/threads/ls1-piston-slap-quandary.80844/
I have been a BITOG member since 06 BTW but my old username was lost somehow and could not be recovered. The thread above was not mine though.
Last edited:
