Maintaining same oil bypass PSI as Subaru OEM?

[StumblingElk]

I'm looking to stock up on oil filters for a 24 WRX.

Factory bypass rating is like 23psi compared to most aftermarket filters at around 15psi

Is running the factory bypass rating really that critical? Is OEM really the best option here?

For reference I've been running 3k to 4k oci on e50 blend and Pennzoil Ultra Platinum 5w30 with a Mobil 1 or Fram TG filter. Switched to Valvoline Restore and Protect last oil change due to availability

 

[JohnnyG]

I think that that spec would only come into play if you let your oil filter plug up and the DIFFERENTIAL pressure across the media exceeded 15 psi. If you keep relatively clean oil in your engine, you should be fine.
In fact, if you run very high oil pressure at high rpm, that lower bypass rating would actually be beneficial by allowing more CLEAN oil to flow without restriction of the filter media.

 

[DCDG]

I'm looking to stock up on oil filters for a 24 WRX.

Factory bypass rating is like 23psi compared to most aftermarket filters at around 15psi

Is running the factory bypass rating really that critical? Is OEM really the best option here?

For reference I've been running 3k to 4k oci on e50 blend and Pennzoil Ultra Platinum 5w30 with a Mobil 1 or Fram TG filter. Switched to Valvoline Restore and Protect last oil change due to availability

I would be curious to hear the answers because I wondered the same thing with the new updated Nissan filters for the vc-t engine. the filters aren't stupid expensive and they're made in Japan by Mahle so they're good filters but curious if there's another choice. I personally feel for whats it worth sticking with OE and knowing the filter wont be in early bypass.

 

[ZeeOSix]

I'm looking to stock up on oil filters for a 24 WRX.

Factory bypass rating is like 23psi compared to most aftermarket filters at around 15psi

Is running the factory bypass rating really that critical? Is OEM really the best option here?

For reference I've been running 3k to 4k oci on e50 blend and Pennzoil Ultra Platinum 5w30 with a Mobil 1 or Fram TG filter. Switched to Valvoline Restore and Protect last oil change due to availability

What filter number in the MicroGard Select would be specified for your engine? I know some of them have a bypass valve set to 22 PSI per O'Reilly's website.

 

[StumblingElk]

What filter number in the MicroGard Select would be specified for your engine? I know some of them have a bypass valve set to 22 PSI per O'Reilly's website.

MSL51334 . Says 8-11 PSI

 

[slacktide_bitog]

The Wix WL10078 seems like what you need

 

[StumblingElk]

The Wix WL10078 seems like what you need

I'm seeing this filter listed with both a 30psi and a 12psi rating

 

[ZeeOSix]

I'm seeing this filter listed with both a 30psi and a 12psi rating

On Wix's website? Think it went through a design change a while back, so you might be finding old and new info.

 

[Dave Hess]

For my Subaru I bought 6 online from a dealer.

I also wanted the correct BPV filter pressure.

 

[StumblingElk]

From what I've gathered by reading older posts here and elsewhere I may have found my answer

It seems that the 23 PSI bypass is likely just a reflection of the filtering material of the OEM Subaru filter itself rather than an engineering decision made specifically for the motor.

Meaning, if Subaru wanted their OEM filters to spec synthetic filtering media like that found in Mobil 1 filters, then the bypass rating would then be lowered.

At least that's my understanding at this time.

Given the flow rate of Mobil 1 or TG/UG filters, short OCI, mild climate, and gently driving the car until the oil is warmed up I doubt a lower bypass rating is going make a difference.

If in doubt I see the microguard select has an 18psi to 20psi rating. IE....close enough

If someone can see the error in my logic I'm all ears, though

 

[ZeeOSix]

If in doubt I see the microguard select has an 18psi to 20psi rating. IE....close enough

If someone can see the error in my logic I'm all ears, though

Per post 5 the MSL51334 showsd 8-11 PSI bypass valve. Think there's an over sized MicroGard Select for that filter with a higher bypass valve setting. I'll verify and let you know later as I need to look at a different computer for the info.

It's true that a filter bypass valve setting is taking into account the filter itself in terms of delta P vs flow and how that changes with debris loading and the expected max dP in use. One filter model typically needs to cover many engine applications. Also you will see many different filters brands specified for the same engine, but they will have different bypass settings so that eludes to the filter itself factor.

It could be the OEM Subaru filter is relatively flow restrictive (ie, has a higher dP vs flow curve), and that combined with some crazy high volume Subaru oil pumps lands the OEM filter at 23 PSI. I wish Brand Ranks would have dP vs flow tested a Subaru OEM filter to see where it ranked.

Yes, keeping the engine RPM down until the oil is hot does a lot to reduce the bypass valve from operating.

 

[StumblingElk]

Per post 5 the MSL51334 showsd 8-11 PSI bypass valve. Think there's an over sized MivroGard Select for that filter with a higher bypass valve setting. I'll verify and let you know later as I need to look at a different computer for the info.

It's true that a filter bypass valve setting is taking into account the filter itself in terms of delta P vs flow and how that changes with debris loading and the expected max dP in use. One filter model typically needs to cover many engine applications. Also you will see many different filters brands specified for the same engine, but they will have different bypass settings so that eludes to the filter itself factor.

It could be the OEM Subaru filter is relatively flow restrictive (ie, has a higher dP vs flow curve), and that combined with some crazy high volume Subaru oil pumps lands the OEM filter at 23 PSI. I wish Brand Ranks would have dP vs flow tested a Subaru OEM filter to see where it ranked.

Yes, keeping the engine RPM down until the oil is hot does a lot to reduce the bypass valve from operating.

Microguard states 15 to 20psi for their Select line

Standard microguard is 8-12psi.

When I made post #5 I was relaying what Google AI came back with. That's my mistake


My belief is that the Subaru OEM filter media is comparatively restrictive. Can't back that up with any good data though

https://microgards.com/microgard-select-oil-filter/

 

[ZeeOSix]

Microguard states 15 to 20psi for their Select line

Standard microguard is 8-12psi.

When I made post #5 I was relaying what Google AI came back with. That's my mistake

My belief is that the Subaru OEM filter media is comparatively restrictive. Can't back that up with any good data though

https://microgards.com/microgard-select-oil-filter/

Here's the info on O'Reilly's website.

https://www.oreillyauto.com/detail/.../30401/automotive-car-2010-mazda-3?q=MSL51334

In the Question & Answers section it says this: 8-11 PSI.

 

[StumblingElk]

Here's the info on O'Reilly's website.

https://www.oreillyauto.com/detail/.../30401/automotive-car-2010-mazda-3?q=MSL51334

In the Question & Answers section it says this: 8-11 PSI.

View attachment 333639

I guess I'm not sure why this is such a sticking point for you.

The manufacturer states that the bypass valve opens at 15 to 20psi. So that's what I'm going with

Seems very likely that the chat bot at O'Reilly was spitting out the setting for the other line of micro guard filters . No?

In either case. Cheers

 

[ZeeOSix]

I guess I'm not sure why this is such a sticking point for you.

The manufacturer states that the bypass valve opens at 15 to 20psi. So that's what I'm going with

Seems very likely that the chat bot at O'Reilly was spitting out the setting for the other line of micro guard filters . No?

In either case. Cheers

Just pointing out other information directly from O'Reilly who specs their MicroGard filters to PGI. I don't think the answers given by O'Reilly's is a "chat bot" but someone actually answering questions, hence the "RG" in the answer signature. You can believe whatever you want, it's your vehicle, not mine.

 

[ZeeOSix]

Microguard states 15 to 20psi for their Select line

Standard microguard is 8-12psi.

When I made post #5 I was relaying what Google AI came back with. That's my mistake

My belief is that the Subaru OEM filter media is comparatively restrictive. Can't back that up with any good data though

https://microgards.com/microgard-select-oil-filter/

BTW, did you see this at the bottom of the main page of that website? It's not an official MicroGard website, so I'd be leery of what they are saying about specs.

 

[StumblingElk]

BTW, did you see this at the bottom of the main page of that website? It's not an official MicroGard website, so I'd be leery of what they are saying about specs.

View attachment 333656

I have no idea what web site you have pictured above. But it isn't from the link I posted


I put almost no weight or significance behind any q&a from big box parts stores, either. And yes, much of that is AI.

For instance, their q&a states that Mobil 1 doesn't release any data on the filtration rating for their oil filters . Which is clearly inaccurate .

Yep. My car . And I'm confident enough for the both of us.

 

[ZeeOSix]

I have no idea what web site you have pictur

It's connected to the same main website you linked in post 12. Go to the very bottom right side of the page linked below. That is not an official MicroGard website, so most likely not totally accurate. I'd trust the question and answers on O'Reilly's website before that unofficial website since they have access to PGI technical information about their MicroGard products.

https://microgard.520hyy.com/

Independent fan-created platform ... not official MicroGard/O'Reilly.

If you go to Premium Guard's website what do they show for the Premium Guard filter specified for that engine?

 

[StumblingElk]

It's the same main website you linked in post 12. Go to the very bottom right side of the page linked below. That is not an official MicroGard website, so most likely not totally accurate. I'd trust the question and answers on O'Reilly's website before that unofficial website since they have access to PGI technical information about their MicroGard products.

https://microgard.520hyy.com/

Independent fan-created platform ... not official MicroGard/O'Reilly.

View attachment 333689

If you go to Premium Guard's website what do they show for the Premium Guard filter specified for that engine?

Purple screenshot is what shows up at the bottom of the page for me on mobile.
The other is the home page. I have no idea where you are getting your pic from. It appears nowhere on the website I linked on mobile. Everything from the verbiage, social accounts, address, etc checks out.

In either case, I'm not worried about it.

Carquest states 15psi.

Hard to believe anything the O'Reilly q&a says when they erroneously state there isn't any micron filtration rating for the Mobil 1 oil filter. Something that could be discovered with 10 seconds on Google

 

[ZeeOSix]

Carquest states 15psi.

The website I saw showed all the same info but has that disclaimer notes as shown, and showed all the same basic MicroGard info - a redirect ( ). Premium Guard's website shows 13-16 PSI (snip-t below, they used PS instead of PSI by error) for the 2024 Subaru WRX 2.4L (PG4459 & PG4459EX). So at least that matches the Carquest Premium bypass spec. The PGI and AAP specs still don't correlate real close to the "15 to 20 PSI" stated by the "MicroGards" website (snap-shot below). Yeah, just don't go nuts on the throttle until the oil is pretty hot.

From PGI website:

Edit - Another aspect is if you trust that the filter maker has specified their correct filter for your application, then go with it. Otherwise, you'd have to conduct your own test program to determine if it was the right specified filter or not.