Subaru Outback Forums banner

21 - 40 of 86 Posts

·
Registered
06 OBW 2.5, 05 Forester, had 03 H6 OBW
Joined
·
5,909 Posts
Wow, I didn't know about the bypass pressure.

Subaru's bypass pressure is over 20psi, aftermarket filters don't have nearly that, that's good enough for me. Especially here where it may be -10F in winter.

So I assume the 'new blue factory fram' filters will have the correct bypass pressure...


Dave
 

·
Registered
2007 Outback 2.5i AT
Joined
·
608 Posts
Ok.. so I see all sorts of opinions on here about what kinda filters you should buy.. So what is the best? Should I buy a case of the old black filters, find a Soob specific aftermarket high quality filter, or stick with the new blue oem filters?? :confused:
 

·
Registered
06 OBW 2.5, 05 Forester, had 03 H6 OBW
Joined
·
5,909 Posts
07OregonOutback said:
Ok.. so I see all sorts of opinions on here about what kinda filters you should buy.. So what is the best? Should I buy a case of the old black filters, find a Soob specific aftermarket high quality filter, or stick with the new blue oem filters?? :confused:
If I knew of an aftermarket filter with as much media, good end-caps and spring, and the proper relief valve I wouldn't hesitate to use it.


Dave
 

·
Registered
My-'06 Outback 2.5 i Limited Wagon & Wife's '08 Outback 2.5 i Limited Wagon
Joined
·
703 Posts
CNY_Dave,

Let me see . . . Wix, Mobile 1, Amsoil . . . to name a few

Regards,
~Button
 

·
Registered
07 2.5i
Joined
·
779 Posts
Button said:
CNY_Dave,

Let me see . . . Wix, Mobile 1, Amsoil . . . to name a few

Regards,
~Button
The bypass valves on those open at way less than 23 psi. That's the whole point of that thread over on BITOG - they don't meet the specs listed in the Subaru factory service manuals.

Otherwise, they are quality filters, and many, many, people have run them for many, many miles without problems.

I'll stick with the OE filter until someone proves that the lower bypass pressure doesn't matter.
 

·
Registered
2007 Outback 2.5i AT
Joined
·
608 Posts
Yeah I agree, I'll stick with the blue filters. If they cause my engine to fail prematurely, Subaru can buy me a new engine.
 

·
Registered
2009 Outback SE, Seacrest Green
Joined
·
27 Posts
My problem is that I'm new to Subaru. I was all ready to use the OEM black filters because there was a great body of evidence throughout the multiple Subaru forums that they were a good filter. I personally have had filter problems with Frams in the past and won't use one so the new blue one is a non-starter for me. If I had never read that thread I would be using NAPA Gold 1356 which is what is on my Outback now.

I understand the technical part of the BITOG discussion somewhat, but the importance to me is lost given that there a lots of high mileage Subies running around on filters that don't meet that spec. One would think if it was so important there would be a lot more failures, aftermarket suppliers would build something suitable, and it would show up as a trend in oil analysis. I just can't find an overwhelming body of evidence that the pressure setting is that important though I'm still concerned about meeting the factory spec.

I picked up a Purolator PL14460 today. It is the older turbo filter before Subaru went the smaller diameter model. It is spec'd at 23 PSID, but has no anti-drain back valve. From what I have read this filter should fit the current 2.5 NA fine. Is anyone with an '08 or '09 using this filter or have a lot more experience with Subarus to know if this is a good alternative?
 

·
Registered
2002 WRX MBP
Joined
·
1,105 Posts
WagonBoss said:

I picked up a Purolator PL14460 today. It is the older turbo filter before Subaru went the smaller diameter model. It is spec'd at 23 PSID, but has no anti-drain back valve. From what I have read this filter should fit the current 2.5 NA fine. Is anyone with an '08 or '09 using this filter or have a lot more experience with Subarus to know if this is a good alternative?
I worked in a Subaru dealership back in the late 90's. Back then, Purolator made the US market Subaru filters that you'd buy from your dealership. ("Factory fit" filter was a black one, Denso made, I think) They where white bodies, said "Subaru" down one side and "Purolator" down the other. Not sure when they switched from the dealers selling those to the black ones, but I'm assuming they were the same ones that came on the cars from the factory.

Ever since I worked there, I've always used Purolator filters on all my Subarus.
 

·
Registered
2005 Outback H6 3.0 LL Bean
Joined
·
1,204 Posts
I agree that the Purolators are great.

When I'm too busy, or it's too **** cold outside, I go the local Quaker State quick lube place, whose filters are rebranded Purolators.

They always put on the QS14461, which I figured was a PL14460. After some more research, I found a forum post by a guy who runs a service garage saying that the QS filter has a bypass valve rated at 12-15psi. So, perhaps not quite as good as I had hoped (couldn't find any hard specs), but still a very good filter and a nice option to have if you're in a rush.
 

·
Registered
07 2.5i
Joined
·
779 Posts
WagonBoss said:

I picked up a Purolator PL14460 today. It is the older turbo filter before Subaru went the smaller diameter model. It is spec'd at 23 PSID, but has no anti-drain back valve. From what I have read this filter should fit the current 2.5 NA fine. Is anyone with an '08 or '09 using this filter or have a lot more experience with Subarus to know if this is a good alternative?
Will the PL14460 fit in the space available? At least for my '07, they wrapped the exhaust around the oil filter just like the turbos, hence the reason for the small diameter filter. I don't know why they did that, it makes oil changes a pain as compared to my old '99 (now my son's). I used the PL14460 on that car with no problems.

By the way, the PL14612 that is listed for our newer Outbacks (and turbos) is spec'd at 14-18 PSI for the relief valve.
 

·
Registered
2001 OB 2.5L Basic
Joined
·
224 Posts
I find this all very interesting apart from all the engineering jargon on "Bobs"....after many years of reading on various web sites as to the poor quality of the "fram filter" and how it should not be used...they (Fram) have amazingly thru "fear" brought over a slew of people who would never use a fram product...It was not that long ago that many oil filters had high pressure valves because a lot thicker oils were used like 15/40 20/50...even 10/30 is to thick and unnecessary with these high pressure oil pumps.....the maintanence oil change required the filter to be changed every other oil change..the cars were carburetored which contaminated the oil much sooner (becoming black and thick) and the list goes on for the reason to have for ex:23psi...but with todays cars that run clean and require thin oil ( 5/30 or less in extreme cold weather) and if reg. serviced should have no fear with the better quality aftermarket names....I tend to look for results in the real word and have my oil checked from time to time at 5000miles just for the fun of it...as I have said before on another post, that useing X/20 oil with an aftermarket filter has only given me above average results as stated by "blackstone"...here in Canada the white filter REplacement is a re-painted fram at 3 times the cost if comparing to walmart ( even the machine milling marks were the same between the two filters)...that kind of "security" rubs me the wrong way ( I meant to say the "pole" from behind )..especially if the replacement filter is different from the one that came from the factory .....probably the best filter out there ( so the porsche people say ) is the K&N or Mobil 1 with the synthetic fiber that lets the oil pass thru much easier especially in high reving or cold start up situations which makes the high pressure valves redundant...in ending, my question to subaru would be... Why was the low pressure re-painted fram filter good before and NOT now...my 2nd question would be...since the subi filter is so important ...are we also now to use there subi branded motor oill
 

·
Registered
2001 H6
Joined
·
224 Posts
CNY_Dave said:
Wow, I didn't know about the bypass pressure.

Subaru's bypass pressure is over 20psi, aftermarket filters don't have nearly that, that's good enough for me. Especially here where it may be -10F in winter.

So I assume the 'new blue factory fram' filters will have the correct bypass pressure...


Dave
I'm no expert, but at -10f, wouldn't your oil will be so thick that even the Subaru filter (spec'd at 23psi) would be in bypass. (thicker oil = greater pressure?)

Speaking of Subaru filters, I emailed Wix Canada regarding this very issue (I've posted a few times in that long BITOG thread) and they seem to think that the white painted Subaru Canada filters (or the blue painted Subaru USA) are just a Fram 3593A filter, which DO NOT meet the Subaru 23psi spec.

Unless FRAM is making 3593A's and *just for Subaru* are placing 23psi bypass springs in the filters, then the Subaru dealer filter is just a FRAM 3593 with a bypass setting of 8-11psi or something and painted white with blue Suburu lettering.

My gut feeling is that FRAM is NOT making stiffer bypass springs JUST for Subaru - easier and cheaper to just repaint 3593A's white after they're made the same way as an orange FRAM 3593A. Now the filter that comes from the factory on a brand new car is black and is not a FRAM - maybe that has a 23psi bypass.

Regardless, my next oil change I will cut open my Subaru dealer filter and compare it with a FRAM 3593 that is new and unopened on my shelf.
 

·
Registered
Joined
·
17,689 Posts
Some time ago I cut open the Subaru Canada white with blue lettering filter that applies to my 07, and compared it to what I saw in the photos of other makes, including Fram, in related earlier threads here and in other Subaru forums. Visually, the Subaru Canada filter parts do look like the Fram, and a number of other makes.

I think you have the right idea, but what is needed is to cut open a new Subaru-brand filter and a new aftermarket (Fram) equivalent (new, in order to eliminate the effects of oil and heat) and not only visually compare them but do some objective measurements; for example, measuring the square inches of filter media in each, as well as the thickness and, if possible, the type of filter material and, relevant to this discussion, whether the Subaru and aftermarket relief valve springs tend to deflect at the same or a significantly different applied pressure. The latter might not confirm the actual relief valve pressure, but will verify whether the Subaru filter uses the same, or a significantly different, spring.

I don't have a Fram filter, but if nothing decisive comes up here or elsewhere in the next while, I'll pick up a Fram and do the measurements. Nothing like seeing for myself.
 

·
Registered
2001 OB 2.5L Basic
Joined
·
224 Posts
rcy said:


I'm no expert, but at -10f, wouldn't your oil will be so thick that even the Subaru filter (spec'd at 23psi) would be in bypass. (thicker oil = greater pressure?)

Speaking of Subaru filters, I emailed Wix Canada regarding this very issue (I've posted a few times in that long BITOG thread) and they seem to think that the white painted Subaru Canada filters (or the blue painted Subaru USA) are just a Fram 3593A filter, which DO NOT meet the Subaru 23psi spec.

Unless FRAM is making 3593A's and *just for Subaru* are placing 23psi bypass springs in the filters, then the Subaru dealer filter is just a FRAM 3593 with a bypass setting of 8-11psi or something and painted white with blue Suburu lettering.

My gut feeling is that FRAM is NOT making stiffer bypass springs JUST for Subaru - easier and cheaper to just repaint 3593A's white after they're made the same way as an orange FRAM 3593A. Now the filter that comes from the factory on a brand new car is black and is not a FRAM - maybe that has a 23psi bypass.

Regardless, my next oil change I will cut open my Subaru dealer filter and compare it with a FRAM 3593 that is new and unopened on my shelf.
I have had the opportunity to cut open both filters (both filters were brand new and never used ) and for the best of me, I could not find any difference between the "white"subi 2.5 NA version of their filter when comparing to the orange fram....a little side note here..when comparing a wix or purolator or nippon to a fram used for my 1986 1.8...the filter material in the fram filter is only half the amount when compared to the other brands..the same goes for my VW diesel..simply far less filter material in that fram...concerning the 23psi filter that comes on the car..( just my gut feeling here ) is a good way to protect subaru because of the wide differences in driving habits (soft pedal to hard nailing the floor) together with the wide differences in outside temps, from extreme heat to extreme cold... its a good way to ensure from subis point of view that the new oil is being filtered, removing the by-products of "brake-in"...I have read some where that Toyota has the same policy..one filter for delivery to the new owner and another filter after that for maintenance....Ford has a similar policy concerning the initial factory oil for their diesels.. oil thin enough to cover all extreme weather situations ...after the first oil change, you are on a different recommendation determined by weather if you so choose...
 

·
Registered
Joined
·
17,689 Posts
The by-pass pressure seems to be the key issue in the discussion here and elsewhere. As I noted earlier, I think some objective measurements might help resolve the question, and I decided to give it an initial try, at least in part.

I had a new, but case-damaged, Subaru Canada oem filter (part # SCI530009), identical to the one I opened and posted a picture of in an earlier filter thread. [ http://www.subaruoutback.org/forums/showthread.php?threadid=16009&highlight=filter ]

The new one has the advantage of being clean and dry inside, and the bypass spring and valve have not been subjected to the heat of a running engine.

I cut the filter open near the fluted end using a rotary tool and cutting disk. This avoided contact with the filter media pleats. I then removed the bypass valve assembly, which consists of a metal "bridge", a plastic valve with four "fingers" and a spring held in the fingers. The valve assembly is visible in the above-mentioned photo at the left end of the filter media pack.

The specification that Subaru has in my 2007 service manual(s), and I believe this has been the same for quite some years for the 2.5 NA engine, reads: "By-pass valve opening pressure 160 kPa (1.63 kgf/cm2, 23.2 psi). From this I presumed that the pressure of 23 psi is pressure on the back of the valve surface, working against the spring. I had no way to simulate fluid pressure on the valve, but I could apply mechanical pressure. To do this I borrowed my wife's beam-balance kitchen scale, positioned the valve assembly with the fingers facing down on a small block of wood on the scale, set the scale to various weights, and then evenly pressed down on the metal bridge until the valve began to open. (See attached photo)

What a surprise. I found that at 7 pounds the valve was clearly open and at 8 pounds it was virtually fully open. (The valve can only move about 1/8 inch above the mating metal surface). I repeated the test several times, and checked the scale against known weights to make sure it wasn't damaged. I even tried the same arrangement using a spring-type bathroom scale with essentially the same results. Eight pounds!

Is this making any sense? Is the way I'm testing the pressure at which the valve opens consistent with what Subaru means by "opening pressure"? Is this equivalent to the psi rating?

I don't have access to the SOA blue filter nor to one of the black oem filters that was available earlier in the U.S. I will try the (Canadian) Fram model for my car, and perhaps also the filter that Wall-Mart Canada has. But a real test of the issue is at what point the SOA blue, and especially the SOA black filter valves open.

Fundamentally, if we can compare a range of makes of filters for the same car, it doesn't matter what our actual readings are. We know that Fram, for example, specs their filter in the 10-14 psi range, whereas Subaru requires 23 psi. that's an almost 2:1 difference. The filter valve I just tested might in fact be a Subaru 23 psi, but only if Frams and other known low pressure aftermarket makes open at 4 pounds, or something like that. Moreover, if an oem black Subaru filter valve tests out at 15 pounds in the same type of test set-up, and both the blue and Canadian white measure in the 7-8 pound range, then we have clear evidence that the new ones have much lower bypass opening pressures which, assuming the black filter met the spec, are well outside Subaru specs. (In other words, even if we cannot confirm the absolute pressure at which the current valves opens, we can establish relatively where they open if we have a known spec-meeting valve.)

So, any one have a black filter for the late MY 2.5 l NA engine, preferably new, to try this simple test measurement on? Anyone want to do the same with one of the SOA blue filters?
 

Attachments

·
Registered
2005 Outback H6 3.0 LL Bean
Joined
·
1,204 Posts
Interesting test...

If you can get a Purolator 14460, it should have the 23psi bypass as well.
 

·
Registered
2013 XV Crosstrek
Joined
·
665 Posts
I picked up a blue Subaru OEM filter from a dealership by my parents this weekend, it does say "honeywell" on it though I haven't even taken it out of it's shrink wrap yet...

Jay
 

·
Registered
'00OBW, '96&'94 Legacy - all rusted RIP, current: 2016 Focus MT
Joined
·
4,804 Posts
Quote: Is this making any sense? Is the way I'm testing the pressure at which the valve opens consistent with what Subaru means by "opening pressure"? Is this equivalent to the psi rating?

That sounds like a good test. The missing part of the equation is the surface area of the bypass valve that would be exposed to the oil pressure.

If the spec is 23 psi (pounds per square inch).

You now know the pounds portion : 7 pounds

Now calculate the surface area exposed to oil pressure. If it were .3 square inches, then pounds / square inch would be 7 pounds / .3 square inches = 23.3 psi



Just another note to add for info for the thread, the Subaru oil pumps (the n/a ones anyway) have an internal relief valve at about 72 psid.
 
21 - 40 of 86 Posts
Top