Beating the horse to death: Subaru and Fram Ultras

[nthach]

A little birdie gave me two FU XG7317s since he insists on OEM filters. I don't own anything that uses a 3593A/6607/7317 filter with a M20x1.5 filter spud mount, all the cars in my family use standard Toyota spin-on sizes. But an old friend I grew up next to have things that will take those filters - a Nissan, Honda bike and 3 Subarus.

We all know Subaru calls for a higher than usual bypass valve setting, around 22-27psi. The Fram rep here, Motorking said that there's enough media in a Fram filter to withstand the delta-P changes that would happen if the filter is in bypass but a FU is a pretty stout filter with dual-layer metal mesh backed media. Newer Subarus are speced for the (PH/TG/XG)7317 filter. I need to change the oil in one of the Foresters this weekend.

Will I be fine with the FU, as much as this topic has been beaten to death?

 

[LoneRanger]

I'd imagine so. I use the OEM blue Subaru filters if only because I can get them at the dealer parts counter for same or less than an after market filter at Advance Auto or whereever. Wix makes one for Subaru's with the right bypass valve psi spec, too.

 

[skyactiv]

There is a legit reason why Subaru chose the bypass they did. Using an oil filter with an incorrect bypass setting because the user wants to use a free or "better" oil filter that fits anyways is being a fool.

 

[nthach]

Originally Posted By: skyactiv
There is a legit reason why Subaru chose the bypass they did.

And you'd think the aftermarket would make a specific filter to help keep powertrain warranties intact. Wix does, supposedly Mahle does as well. But Fram doesn't, seeing how they supply the service filter(at least not for the EJ25/Fx20/FB25 for the aftermarket, they do make a PH9715 for the WRX STI or the EJ20 with the proper spec, why not market that instead?).

And there's a ton of Subarus that go to the quick lube and get a 3593A or 6607/7317 sized filter installed.

 

[mx5miata]

I had a 2010 Subaru Impreza 2.5 non turbo and used Wix oil filter for the 3 years I leased the car never ran into an issue. Maybe I was just lucky.

 

[SubieRubyRoo]

NAPA/WIX 7055 for FB25s, has a 27# bypass.

 

[nthach]

Originally Posted By: SubieRubyRoo
NAPA/WIX 7055 for FB25s, has a 27# bypass.

And I can get Wix from one of the parts houses or O'Reilly. I can also use the Toyota/Denso 90915-YZZS1 filter for the FT86/FR-S as well - I can get them cheaper.

 

[Pelican]

Originally Posted By: skyactiv
There is a legit reason why Subaru chose the bypass they did. Using an oil filter with an incorrect bypass setting because the user wants to use a free or "better" oil filter that fits anyways is being a fool.


Gee I didn't know this! Would this apply also to a 2001 MY Outback? I've been using Mobil 1 filter for years as I though the OE element not good enough.

Please advise. Thank You

 

[SubieRubyRoo]

Subaru OEM filters have always been very good, and they have always had 24# bypass for EJ engines (such as your Outback) and the newer FB25s specify a 27# bypass. Subaru oil pumps are high-flow, and therefore require the high bypass pressure to prevent passing unfiltered oil through the engine during cold starts.

 

[TTK]

Originally Posted By: SubieRubyRoo
Subaru OEM filters have always been very good, and they have always had 24# bypass for EJ engines (such as your Outback) and the newer FB25s specify a 27# bypass. Subaru oil pumps are high-flow, and therefore require the high bypass pressure to prevent passing unfiltered oil through the engine during cold starts.

This is very true. Their oil flow is unbelievably high for a car.You are better off using OEM Subaru or Wix/NAPA Gold.

 

[slacktide_bitog]

There is a Wix XP/Napa Platinum for this Subaru application, and Napa has them on sale right now for $9, same price as Fram Ultra

Napa Platinum 47055
or
Wix 57055XP

 

[Gebo]

I'm with skyactiv until the last word in his reply. I would substitute "dumb donkey" for "fool."

 

[Linctex]

If you ever see 27 PSID in a subaru oil filter..... I'll eat that thing.

What a bunch of hokey hogwash y'all been swallowin'.......

 

[The Critic]

I might have some OE Subaru filters as well, but that would require me to dig. Next time.

 

[Pelican]

Thanks to all who replied! Will go back to OE oil filter.

 

[SubieRubyRoo]

Originally Posted By: Linctex
If you ever see 27 PSID in a subaru oil filter..... I'll eat that thing.

What a bunch of hokey hogwash y'all been swallowin'.......


Linc, I think I have agreed almost entirely with your stance on nearly all your posts I have read until this one.

Please, do tell, why would they specify 24/27 psi bypass if it wasn't necessary? Certainly a bypass that is double what other filters call for will require a heavier-duty media, which will further increase costs. I don't see any manufacturer, much less one that had historically only sold ~150k cars a year, to make unnecessary requirements which likely doubles the cost over a "regular" 8-13# bypass filter. But I'm all ears to learn if you have answers

 

[ZeeOSix]

Originally Posted By: SubieRubyRoo
Originally Posted By: Linctex
If you ever see 27 PSID in a subaru oil filter..... I'll eat that thing.

What a bunch of hokey hogwash y'all been swallowin'.......

Linc, I think I have agreed almost entirely with your stance on nearly all your posts I have read until this one.

Please, do tell, why would they specify 24/27 psi bypass if it wasn't necessary? Certainly a bypass that is double what other filters call for will require a heavier-duty media, which will further increase costs. I don't see any manufacturer, much less one that had historically only sold ~150k cars a year, to make unnecessary requirements which likely doubles the cost over a "regular" 8-13# bypass filter. But I'm all ears to learn if you have answers

A few theories: 1) Subaru filters could be pretty flow restrictive, so they bumped up the bypass setting to ensure less bypass events. 2) Subaru might think their customers are heavy footed with the engine RPM right after a cold start-up in colder climates. 3) Turboed Subarus do put out lots of oil pump flow at high RPM - that's been discussed in many threads. 4) A combination of 1) thru 3).

IMO, when the oil is at full operating temperature the delta-p across the filter will be very far away from the bypass valve setting - even at 12 GPM if the pump is actually putting out that massive flow amount. If the oil is very cold and high engine RPM is used, delta-p will be much higher ... as high as 24~27 psi? Only a delta-p gauge across the OEM filter in those conditions would tell for sure. The same delta-p gauge test would have to be done with many filters to see how they compared to OEM in terms of delat-p vs flow vs oil temperature/viscosity.

 

[LoneRanger]

Originally Posted By: TTK
Originally Posted By: SubieRubyRoo
Subaru OEM filters have always been very good, and they have always had 24# bypass for EJ engines (such as your Outback) and the newer FB25s specify a 27# bypass. Subaru oil pumps are high-flow, and therefore require the high bypass pressure to prevent passing unfiltered oil through the engine during cold starts.

This is very true. Their oil flow is unbelievably high for a car.You are better off using OEM Subaru or Wix/NAPA Gold.


I have the specs on the oil pump flow in liters per minute or whatever, buried somewhere in the dusty corners of my laptop's hard drive. I'll try and find it. It's a page in the Factory Service Manual PDF for my '09. Moves a lot of oil.

 

[LoneRanger]

That didn't take long ... found it. Here's a screen cap from the 2009 Forester Factory Service Manual for EJ25 non-turbo. It's in quarts per minute. 47 @ 5000 rpm. bypass pressure spec on OEM filter 23.2 psi. The newer FB engines have a 27 psi bypass spec.

 

[BufordTJustice]

Originally Posted By: ZeeOSix
Originally Posted By: SubieRubyRoo
Originally Posted By: Linctex
If you ever see 27 PSID in a subaru oil filter..... I'll eat that thing.

What a bunch of hokey hogwash y'all been swallowin'.......

Linc, I think I have agreed almost entirely with your stance on nearly all your posts I have read until this one.

Please, do tell, why would they specify 24/27 psi bypass if it wasn't necessary? Certainly a bypass that is double what other filters call for will require a heavier-duty media, which will further increase costs. I don't see any manufacturer, much less one that had historically only sold ~150k cars a year, to make unnecessary requirements which likely doubles the cost over a "regular" 8-13# bypass filter. But I'm all ears to learn if you have answers

A few theories: 1) Subaru filters could be pretty flow restrictive, so they bumped up the bypass setting to ensure less bypass events. 2) Subaru might think their customers are heavy footed with the engine RPM right after a cold start-up in colder climates. 3) Turboed Subarus do put out lots of oil pump flow at high RPM - that's been discussed in many threads. 4) A combination of 1) thru 3).

IMO, when the oil is at full operating temperature the delta-p across the filter will be very far away from the bypass valve setting - even at 12 GPM if the pump is actually putting out that massive flow amount. If the oil is very cold and high engine RPM is used, delta-p will be much higher ... as high as 24~27 psi? Only a delta-p gauge across the OEM filter in those conditions would tell for sure. The same delta-p gauge test would have to be done with many filters to see how they compared to OEM in terms of delat-p vs flow vs oil temperature/viscosity.


Having spoken with Fram tech about this issue for my 2011 Outback 3.6R (and my old '99 Impreza OBS EJ 2.2), they stated, clearly (as has MK) that the delta-P across the FU filter media would be within spec for the Subaru bypass specs due, specifically, to the markedly lower media restriction in the FU filters compared to cellulose fiber media or hybrid media.

The bypass spec was based on a filter media of a certain restriction. This was and is paper media for the OEM filters. Synthetic media has superior flow characteristics, so the same bypass setting is not required.