Can I use 0w30 oil instead of 0w20?Subaru 2.5/2021/leased?
0w20 or 0w30
- Thread starter Joeescape63
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Film thickness protects not harms. No oil with a somewhat higher HT/HS is going to harm any engine.
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I agree: if you’re leasing, let the next guy figure it out. This is why I don’t buy used cars unless they’re headed to the track.
A lot going on there not all of which is true. Where’d you get all that?
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What isn’t true? Did you report the post because it’s been deleted.
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Not AI. Real person.
Yes, again.
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Good rule of thumb is to stick with the first number (0w in this case) and be able to move up one or two grades safely (from 20 to 30 or 40).
However, this is an estimation of safely recommending a change from OEM recommendations.
You have to look at bearing tolerances and what kind of metals are used in the engine itself as they heat up and expand at different rates, amounts, and times.
Subarus start out with pretty tight clearances when cold (not as tight as a Ferrari, not as loose as a Mazda). You want easy flow, so keep it at 0w. They’re aluminum engines, which heat up quickly and expand faster than the crank’s and piston’s material, so there’s a period of “loose” clearances. Most of your blow-by, fuel dilution, and condensation happens around this time and takes about 20min of driving to normalize depending on the weather.
When everything is heated through, you’ll have normalized clearances which will be in the neighborhood of what the OEM references as spec. For the Subaru, its normal operating temperatures puts it right between a 0w20 and 0w30 multigrade oil, so even when you do the research the answer isn’t an easy one. If you want to FAFO with different grades of oil, a lease is a great way to do it… but I’d also send in oil samples to Blackstone to keep yourself (and others) informed. Could be an interesting long-term experiment.
Certain viscosities provide certain “cushion,” but any 0w base isn’t going to be as thick as a comparable 5w at operating temperatures. I.e., 0w20 is going to be thinner than 5w20 at 220 degrees. The only exception is Pennzoil’s Platinum, which advertises 5w protection from a 0w base. I don’t know if this has been independently substantiated, but it is a really good oil.
Mobil1 makes a 0w30 that is GF6 and API SP certified, so it’s applicable to the Subaru’s engine (I also drive a Subaru, so I’ve looked into this). They also make a 0w40 for European cars. It doesn’t have the ILSAC and API certs, nor does it have the Dexos cert (at least to my knowledge). They make a 0w40 for the Corvette that has Dexos 2 Gen 1 certification that may be GF6 and SP certified.
For me, after all my research, I stick to Kirkland 0w20 and buy cases of it when it goes on sale. It’s GF6 and SP certified and made by Warren, so it’s a good oil. I do 4.5k OCIs because I split the difference between normal and severe operating conditions and use WIX XP filters because they offer the best filtration with the closest bypass specs to the Subaru blue filters (which are crap now that they’ve contracted FRAM to make them).
To get around the major weakness of the FB25, I take some extra steps to keep it from getting gunked up or blowing RTV.
Every 5 oil changes I run LiquiMoly Engine Flush through as preventative care. This keeps my oil control rings from getting gummed up with carbon from the DI soot. After the flush, I run a treatment of LiquiMoly’s Ceratec to build in a little extra (possibly total placebo) wear protection for oil dilution (DI blow by) and higher temps (I see temps approaching 225 when driving for long periods on the highway in summer).
I fill it to 75% the dipstick when I change oil. This keeps oil aeration to a minimum, which reduces crankcase pressures and improves fuel economy slightly (less drag on the crank), but also avoids the dreaded turn right oil starvation of the FB25 seen on the 86 and its derivatives.
I change the PCV valve on the 6th oil change to make sure everything is working correctly and I don’t suffer a high crank pressure failure (blowing out RTV seals: only gasket is the head gasket).
And here’s the last bit: I run a catch can. This is reported to void the warranty, so do so at your own risk… however I also travel with what I call a Back To Stock kit so I can change it out while waiting for a tow truck if I needed warranty service. Not saying you should do this, just sating…
Over the last few cycles of this protocol (started with it brand new) I’ve noticed some consistencies. For the 1st and 2nd oil change following a flush, the catch can stays relatively dry. The 3rd oil change sees about 10mL of captured blow-by, and it climbs about 10% for the 4th and 5th oil changes (13 and 18-20mL respectively). This indicates some contamination of the oil control rings (my hypothesis, anyway).
When I flush the engine, I do see a little bit of grittiness from soot being washed out of the engine. My guess is that it’s coming from the oil control rings as blow-by all but disappears following the LM treatment.
I also do intake treatments every 30k miles (per the officially unofficial Subaru recommended service guide… and I do this immediately before the scheduled oil change) and can back up (through extrapolation) that my modifications and protocols are working.
When I pull my throttle body, there’s very little carbon on the back of the plate and I’ve boroscoped the intake to look at the valves. There’s very little carbon at 30k, so I’m considering extending this to 40k or even 50k intervals and am happy to see the catch can is doing its job and keeping my intake system cleaner than it would be otherwise. This is obsessive overkill since Subarus aren’t known to have a lot of carbon fouling on their intake valves, but you’re probably noticing I’m obsessive about preventing problems with strategic maintenance.
I’m also a pilot. Lol.
The spark plugs at 60k looked like they were brand new and I haven’t developed any leaks (though it’s hard to tell because I have my Outback Krowned every year. Yes… this voids the rust warranty, but so does driving in salt. No joke. It’s worthless from any manufacturer).
It doesn’t burn any oil (at least appreciably that I can see on the dipstick) and has returned 29.38mpg over the course of its life with me (coming up on 80k). I drive 10%+1 over the speed limit and keep up with traffic around town (5-10MPH over most of the time), so I’m not babying it OR flogging it (usually… though I do romp on it sometimes).
I changed to an AEM DryFlo air filter because I like the idea of a reusable filter and clean the MAF every 10k miles (though it doesn’t need it). I’ve seen no abnormal wear from any of the Blackstone analyses I’ve had done, nor do I see any particulate in the intake tube. I don’t care about any HP gains (you won’t find any, anyway) or economy increases (same: no benefit). I just like the idea of reducing waste and saving a few bucks over the long-run.
The only other operating mod I installed is a ValvoMax drain. I do 10-15 oil changes annually on just my own car, so saving 15min in clean up pays for itself. I do, however, pull the actual plug out when doing an engine flush. This gets me about 300mL of additional drainage. Not much, but I’d rather fewer leftovers of the flush be in the system. I seal it back up with an OEM crush washer and Bob’s your uncle.
So you have your anecdotal long-term case study: I’ve used Kirkland 0w20 for the life of my Outback and she’s running great. You can go ahead and FAFO with other multigrade oils, but I wouldn’t worry about it. These are stout motors as long as you think ahead and adjust your preventative maintenance around the engine’s weakness.
When it’s time to change my coolant, I’m going to add an engine block heater and probably a can of water wetter or something to take my summer operating temps down and speed up the warm-up process in the winter. Again: treat the weaknesses and let it run.
If anyone would like to debate what I wrote, feel free. I welcome the learning experience.
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If you disagree with something, challenge it. Don’t just report it and have it stricken. If I’m wrong, let me know why so we can all learn.
I clearly stated my results are anecdotal and may be resultant of things I don’t know.
I’ve read that there are a lot of snowflakes on BITOG, but I didn’t expect my first post to trigger one of them.
If I’m wrong, show me why. If all you can do is troll report, let someone else tell me why I’m wrong.
That’s how learning works.
That’s how community works.
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Good thing you saved it!
First, you expose yourself as a troll with the dig at Fram when this thread has nothing to do with that. You just wish to let everyone know about your bias since you believe it makes you appear more informed.
First, you expose yourself as a troll with the dig at Fram when this thread has nothing to do with that. You just wish to let everyone know about your bias since you believe it makes you appear more informed.
This is not correct. Many examples exist of same-grade oils being thicker at operating temperature with a 0W winter rating. What Pennzoil has to do with it I'm not sure.
It's not tolerances. And for the most part "flow" is never an issue. Besides, it is completely temperature dependent. The only time an oil with a 0W winter rating is guaranteed to be thinner is below about -35. Flow only matters in the vicinity of the oil pump pickup tube and then only at low temperatures.
You can safely move up to any grade as long as the winter rating is appropriate for the starting conditions.
API does not issue certifications.
And?
If you are using coolant already and not just plain water, it won't do either one of those. Coolants already have surfactants in them. And besides, unless your cooling system is out-of-bounds open then the operating temperature of the engine is determined by the thermostat set point. No water wetter will change that.
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I’m sorry I hurt your feelings.
FRAM filters aren’t the best. That’s not trolling… unless you’re a shill. Some of their filters are good, but their filtration and bypass valves for even their premium lines aren’t compliant with Subaru OEM specs. The new American blues made by them aren’t as good as the previous units. It’s well known in the Subaru community.
That’s not trolling. That’s facts. If it is objectionable to your opinions, take it up with the analysis by MrSubaru. The SOA filters FRAM is making for Subaru are inferior to the previously sourced parts.
Pennzoil advertises their 0w protects like 5w at cold temperatures while flowing like 0w. It’s on their bottles. Anyone can see it.
Furthermore, lower base oil viscosity DOES, IN FACT translate to lower multigrade viscosity. ProjectFarm did an entire video on this.
Bearing clearances/tolerances do have something to do with oil flow. That’s why you can’t run 50w straight oil in everything. If an oil is too heavy, it won’t lubricate effectively at target temps. This is why manufacturers make recommendations and oil fill caps don’t have “Whatever you want” stamped on them.
A multigrade 50 won’t lubricate the same as a multigrade 20 at normal operating temps the same as 10w won’t lubricate the same as 0w at cold temps. Clearances are why engineers dictate the viscosity recommendations for any piece of machinery. It’s why there are a lot of different grades and types of oil. If it didn’t matter, why would companies go through the expense of having different production lines?
You cannot move up to any multigrade rating you want. Ask anyone that does endurance racing. If an oil is too heavy, it’ll kill an engine just like an oil that’s too thin. If my engine with its bearing clearances was operating at 250+ degrees, I could run 0w30 or 0w40… but it doesn’t, so I stick with multigrade 20. I consulted the charts from Driven Racing Oils to inform my decision.
If API doesn’t certify oil, why are there API SN and SP certifications on motor oil containers? Why do they have their own logo and seal?
If API doesn’t certify oil, why do the have their EOLCS system?
For the kids in class that don’t know, that stands for Engine Oil Licensing and CERTIFICATION System.
Also said I was CONSIDERING adding water wetter when I change my coolant, not that I have decided on it. I haven’t researched it enough, so thank you for your input… but based on everything else you’ve stated for feelings behind you striking my post, I’m definitely going to seek more opinions.
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You’re in deep that’s all I can say. Nearly every paragraph contains errors and many are repeats from your first one.
Welcome back. You should be well versed with the snowflakes here by now.
Welcome back. You should be well versed with the snowflakes here by now.
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In deep? Lol. Is that a threat? Really? Ok dude. Cool story.
I’ve done my research and seen the results. I’ve freely admitted those results could have different causes than why I suspect.
If I’m wrong, show me why.
Otherwise your opinions are empty and should be dismissed by anyone unlucky enough to encounter them.
OVERKILL
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CLEARANCES
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Typo. I’ll correct. Thanks for pointing out my mistake.
It’s not a typo it’s a misunderstanding. Which permeates the rest of your posts.
OVERKILL
$100 Site Donor 2021
It's not a typo, it's mistake/misuse that MANY people make, and it's usually done just before they tell everybody else how wrong they are.
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