Filter for Subaru

Messages
37
Location
wv
I read the symposium that was written a while back about the filter debacle. Of course I didn't read it all. Question: Is it safe to use WIX, K&N, Pulrolator or other....Or should a Subaru owner use an OEM filter. Thanks
 

Bill in Utah

Staff member
Messages
12,849
Location
UT
I've got 25k miles on my 2007 Outback. I know its not a lot of miles but it has only seen a OEM filter for the first 1k miles. Mostly used Supertech ST6607 which work perfectly and I've opened up every one and all is ok. Used a Purolator Pureone and white can and they are a little longer so the element sits closer to the cat. Bill
 
Messages
2,371
Location
WA
 Originally Posted By: 3oilmat1
I read the symposium that was written a while back about the filter debacle. Of course I didn't read it all. Question: Is it safe to use WIX, K&N, Pulrolator or other....Or should a Subaru owner use an OEM filter. Thanks
If you came away from the 18 page discussion with anything, it should be that there is concern that using an oil filter with a much lower bypass setting than the Subaru specified 23 psi setting may cause much more unfiltered oil to circulate through the engine under certain operating conditions. What needs to happen for concerned owners is to have WIX, K&N, Purolator, etc actually address this issue with the high oil volume Subaru's and specifically tell the owners that a 8 ~ 11 psi bypass setting is not going to be in bypass any more than a 23 psi bypass setting. IMO, the 8 psi bypass setting is too low for the oil volume that the Subaru's supposedly puts out (up to 12 gpm) - unless the filter has super low restriction to flow. I can't see how a Subaru OEM filter would be any less restrictive to oil flow than say a WIX or NAPA Gold ... so this tells me that the 23 psi bypass setting is primarly due to the oil volumes seen by the filter. Now get the aftermarket filter makers to tell you that ... if they will even care to address the issue.
 
Messages
622
Location
42.4N 85.7W
 Originally Posted By: SuperBusa
IMO, the 8 psi bypass setting is too low for the oil volume that the Subaru's supposedly puts out (up to 12 gpm) - unless the filter has super low restriction to flow.
Or you're using a much larger filter. In my case a Motorcraft FL-400S. DON'T try this at home :) the threads are different. Dave
 
Messages
192
Location
Northern Virginia
The problem is there is no aftermarket filter that meets all the current Subaru specs in terms of size and pressure relief valve for the 4 cylinder engine. The OEM is the only one. There are some 6 clinder equivalents available. An owner has to decide if the Honeywell OEM filter makes you sleep at night, or a better made Wix that doesn't have the correct by-pass valve setting makes you sleep at night. I don't like the choices. My take is that OEM is probably a better choice if your under warranty. Because I can find no real world issues with aftermarket filters on this engine I will use something else at the end of the warranty.
 
Messages
622
Location
42.4N 85.7W
 Originally Posted By: sw99
Is it the same case for my 1997 Legacy 2.2L?
Is WHAT the same? As for aftermarket filters, that's all my Impreza has ever had since I removed the OEM filter at about 1k miles. It currently has over 211,000 miles on it.
 
Messages
2,371
Location
WA
 Originally Posted By: n8wvi
 Originally Posted By: sw99
Is it the same case for my 1997 Legacy 2.2L?
Is WHAT the same? As for aftermarket filters, that's all my Impreza has ever had since I removed the OEM filter at about 1k miles. It currently has over 211,000 miles on it.
What's the max oil pump volume output and filter bypass spec on the older Subarus?
 
Messages
5,297
Something interesting to note is that in model year 2006 two things happened with the 2.5 liter four cyl engine: Subaru made i-AVLS (intelligent-Active Valve Lift System) standard equipment, and they specified the smaller size filter as the OE filter. The i-AVLS variable valve timing is actuated by oil pressure.
 
Messages
177
Location
New Jersey
 Originally Posted By: LoneRanger
Something interesting to note is that in model year 2006 two things happened with the 2.5 liter four cyl engine: Subaru made i-AVLS (intelligent-Active Valve Lift System) standard equipment, and they specified the smaller size filter as the OE filter.
One other thing happened at the same time: They changed they exhaust routing on the NA H4s. It wraps around the oil filter, just like on the turbos. There is not enough space for the older, larger filter. For the older NA H4s (2005 and earlier), the Purolator Pure One PL14460 fits and the bypass valve is spec'd at 20-25 PSI. But it has no anti-drainback valve.
 
Messages
3,855
Location
Cape Cod, MA
 Originally Posted By: 3oilmat1
I read the symposium that was written a while back about the filter debacle.
Can someone please post a link to this "filter debacle"? Yes, I tried searching...
 

Bill in Utah

Staff member
Messages
12,849
Location
UT
 Originally Posted By: ron917
 Originally Posted By: LoneRanger
Something interesting to note is that in model year 2006 two things happened with the 2.5 liter four cyl engine: Subaru made i-AVLS (intelligent-Active Valve Lift System) standard equipment, and they specified the smaller size filter as the OE filter.
One other thing happened at the same time: They changed they exhaust routing on the NA H4s. It wraps around the oil filter, just like on the turbos. There is not enough space for the older, larger filter. For the older NA H4s (2005 and earlier), the Purolator Pure One PL14460 fits and the bypass valve is spec'd at 20-25 PSI. But it has no anti-drainback valve.
For others who may not have one or seen the new 2006 and later oil filter and header/car routing; 2007 Outback 2.5l NA Bill
 

Bill in Utah

Staff member
Messages
12,849
Location
UT
 Originally Posted By: RF Overlord
 Originally Posted By: 3oilmat1
I read the symposium that was written a while back about the filter debacle.
Can someone please post a link to this "filter debacle"? Yes, I tried searching...
Thread about subaru filters. I've run "normal" filters in my 2007 NA 2.5l outback with no issues @ 25k. The few UOA that I have run have been fine. I'm NOT concerned. Bill
 
Messages
5,297
 Originally Posted By: Dyoel182
Perfect spot to smack a hole in the bottom and let it drain while it cools down AND minimizes the mess.
Exactly what I did. I got it loose enough to turn by hand, then I used an awl to punch a hole in the center bottom of the filter, and let it drain into the catch pan. Once it finished draining, I spun it off. Zero oil splash anywhere on the heat shielding or elsewhere.
 
Messages
649
Location
Maryland
 Originally Posted By: LoneRanger
 Originally Posted By: Dyoel182
Perfect spot to smack a hole in the bottom and let it drain while it cools down AND minimizes the mess.
Exactly what I did. I got it loose enough to turn by hand, then I used an awl to punch a hole in the center bottom of the filter, and let it drain into the catch pan. Once it finished draining, I spun it off. Zero oil splash anywhere on the heat shielding or elsewhere.
Man I wish I had read this awhile ago. I do my own oil changes and I have spilled oil on my exhaust while doing the change. I smell oil for 2 weeks even after I have cleaned off most of the oil (that I can see). Has anyone else had this problem spilling oil on the Subie exhaust? I use a towel now and wrap it around the filter before I change the filter. Still get a little spilled though.
 
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