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why oil filter so tiny??

19K views 60 replies 23 participants last post by  Rub 
#1 ·
Just switched back from purolators to subaru blues (15208AA12A) and boy these things are way smaller than the yellow purolators. any reason? Had me double and triple checking if these were the right ones.
 
#3 ·
Wix makes a good filter…..i use them on my SVX, BRAT, CRX, Civic etc….the black painted ones… Subaru ones are now basically fram (CRAP), and they are not the best of the lot.../
I don't/ wont't use FRAM on any of my cars.. they fall apart and have substandard stuff.
-a smaller filter usually has less filtering capacity. And that mean less ability to do what the engineers want. The low pressure/anti drain back valve bypass is what is VERY important on any filter and the cheap Fram doesnt have it. That can kill an engine.
 
#4 ·
Times have changed and Fram is no longer synonymous with death to your motor and hasn't been for quite some time.

The Fram Ultra is a very good filter and on par with the best of the best. In terms of pure filtration ability and gram of cooties it can hold, it has roughly 30k worth of capacity. Obviously smaller filters hold less but it stands for the point that Ultra filters are extremely good. If you can find me an engine failure or shortened life or decreased filtering I will be extremely shocked.

Don't take my word for it since BITOG has many, many references and biposies of the filter. They aren't expensive and are equal to the RP, M1 or Amsoil filters, among others.
 
#9 ·
don't post on here if you don't know what you are talking about.
Same to you.

Provide evidence of your claims (didn't I have this argument already?).
 
#6 ·
I didn't say the orange can. I said their Ultra.

You have any pics of an Ultra that supports your view that Fram is garbage? You won't find one and you won't find a UOA where the Ultra didn't do the job with dissection of the filter.

I'm going out on a limb but I'll venture that you made your mind up on Fram years ago and it's outside of your comfort zone to think otherwise.

You're not in charge of all knowledge and to confirm that, can you say with 100% confidence that the Ultra is a horrible filter with any kind of science or filtration results to back up the assertion?
 
#12 ·
FWIW, that is very old info.

Also, the H6 filter does fit an EJ. But.....don't use it on turbo EJs. The turbo EJs have a small filter due to close proximity of exhaust manifolds/headers. Being the turbo is of the same side as the filter doesn't help either.
I can't attest to the quality and spec of the Wix unit but the OEM 2009+ Mazda RX8 filters is a fine piece.
 
#13 ·


I use the Subaru OEM blue.
 
#14 ·
Hey all, didnt want to start a fire thread on oil (which like religion or politics it usually does for some reason) so to those who hijacked the thread you have freedom of speech but do me a favor and start your own thread and shoot at each other there yah?

Just wanted to know why these suby blues were so tiny compared to others.
 
#24 ·
Size of a filter is not a relevant metric.

Media amount, media type, media efficiency, filter bypass spec, anti-drain back valve, etc. Those may all mean something.

Size of can is nearly irrelevant.
 
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#28 ·
Size of a filter is not a relevant metric.


Size of can is nearly irrelevant.
See folks, our Moderator assures us, size does not matter...of course, there are no women in this discussion...so....

Now when it comes to size of can(s)...I have to disagree...(big enough to cradle a cell phone?)
 
#30 ·
This is a Hatfields vs McCoys type of question. The black filter is fine for the purpose for which it is intended. It is not a high end filter and never will be but it meets specific requirements that Subie deems important.

That said, other filters have better filtering media, lots of cootie holding room, flow extremely well and do much better on a longer term basis without compromising filtration a single bit. Another point of contention is the high bypass setting of 23 lbs. That's a Subie spec too although both Mobil1 and Fram (they make the blue Subie filter) say they are well aware of the spec, their filters have very high flow properties with excellent filtering through synthetic or hybrid cellulose/synthetic media that ensures that their lower bypass filters function and protect extremely well without comprosing your engine.

IMHO, the Subie filter is designed for a limited service life of around 6-7.5k miles and to meet that spec, you don't need to have a high end filter. You need a capable filter at a certain price point and that's what you get from them. M1 or Fram with the Ultra far exceed the Subie filter in every conceivable factor that forms the basis for good filtration. Fram's Technical Director posts on BITOG and he says, whenever it comes up, that the Ultra filter actually is good for around 25 to 30k miles (depends on can size) but they recommend going only up to half that for lawyer purposes. I personally have never used a Subie or other car manufacturer's filter once the first one came off. It's either the M1 or the Ultra.
 
#32 ·
If the filter is being changed each time with each oil change as recommended, filter size should not be an issue .
If not its just penny pinching - asking for trouble later. Just like timing belt issues - reluctance to do required changes to necessary components in time / before time.
 
#42 ·
Ok, I cant resist.
The original question is WHY is it so tiny?

Einstein once said "I am more interested in HOW things work, than WHY.

let me explain. A Why question is not a very useful way to learn because it makes assumptions that are based on ignorance (not stupid, just uneducated). Also the Why question is implicitly judgemental, as if small is bad.

What matters is HOW well the small filter works. We have been told it actually filters very well for its intended service life.

I would venture that the small filter has different material inside. You could call it higher quality, or denser, or more fine pored, or whatever other adjectives describe the fact that a smaller amount of material is apparently able to do the job that a larger filter with "inferior" material, did in the past.

There are also reasons why a smaller filter has advantages in terms of not being as close to sources of heat, or interference.

So, the bottom line is How Well does the small filter work? So far the importance of Oil Analysis has not been emphasized enough. No amount of explanation, opinion, or speculation about the effects of size, can come close to the amount of factual information available from actual oil analysis.

Here is my suggestion to the OP. Send an oil sample to Blackstone labs. Do it with various filters you are interested in comparing. Oil analysis is the metric that really determines whether the system is working as designed.

I think you will find that the small filter does a very good job, and you can then stop worrying about the size issue.

To put it more colorfully
the oil filter is so tiny because the magic inside is more powerful :)

good luck putting the assumption that bigger is better, aside. I know I have trouble with that. And I dont for a minute believe when men say that women say that size does not matter. I definitely want my package to be as Big as possible :). Its a guy thing..LOL!
 
#43 ·
Jon,

To back up your suggestion on a UOA, those interested can find many results on BITOG that support the idea that the quality of the filter is what matters and some of these filters are very good at their job. These little filters work quite well and you don't need to go oversize or worry about filtration if you buy a quality one.
 
#45 ·
Long ago I decided to trust Subaru's engineering. If they think their filter is good enough, I'm not in much of a position to challenge them.

Both of my Subarus came to me with over 100k on each of them already, both of them came with ordinary stock filters. These cars are obviously surviving (if not thriving) with small filters on them.

They aren't 10-ton trucks. The engine block doesn't trace its lineage to anything designed in the 1950s. Why would the parts be sized for anything from that era?

I use generic filter replacements (the mann 1014 is generally under $3/ea at rock auto) and can't tell any difference apart from the money saved- now over 100k miles driven on those between the two outbacks I've owned.

I think many owners overthink it.
 
#48 ·
Long ago I decided to trust Subaru's engineering. If they think their filter is good enough, I'm not in much of a position to challenge them.
...
Nice, trust the engineering of a company that sold generations of cars with faulty head gaskets when they had quality multi layer steel head gaskets that fit perfectly, but decided to put them in turbo models only. Regardless of engineering, there's always a bean counter who wants to save a few bucks a car. Sounds like the small oil filter is a way to save money in parts stocking when some models would benefit from a larger filter.

I noticed the business end of the Fram Tough Guard oil filter on my daughter's 1.8 L Civic looks exactly the same at the 2.5 L outback filter, right down to the threads, holes, gasket, and diameter. But the filter for the smaller engine is 1/3 longer. Would I be better off using it in my Outback? Maybe not because it may be engineered for different pressures & bypass. Could I go longer between oil changes with today's high quality synthetic oil with a bigger filter membrane? Absolutely. One thing I can say for sure is that the oil in her car stays cleaner looking a lot longer than in my Outback!
 
#46 ·
Talk about over thinking. When I "remoted" my oil filter, I could have easily done a dual filter. Then I thought to myself why, that little blue sucker has done a great job. Just about every single Subaru oil change I have dine has been a Subi Blue.

I just "wanted" the opportunity to run one of the higher capacity Mazda. Running (20 would just have been bragging rights. I certainly need none of that
 
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