Risks of running a lower pressure bypass

[JoelB]

My wife and i both have the small engines that chevy requires using the higher bypass rated filters. I think its 21 psi or something close. I know this has talked about a lot but what are the actual risks of running a "standard" bypass rated filter? Would you be more likely to switch over to bypass mode even with the filter not being full of crud?

What makes this confusing for me is that in our manuals it calls out the UPF64R filter, but both cars were equipped with he PF64 "standard" bypass rated filters from the factory. I don't mind using the UPF64R filter but i would really prefer to run the XG10060 filter which i believe is a cross reference for the PF64.

 

[4WD]

Not sure if you have about 3/4" extra room on length … but Baldwin B7449 has a 20 psi PRV and so does the 20-500 Royal Purple if money is no object …

 

[dwendt44]

With that thin oil, you shouldn't have a problem with a filter going into
bypass. Even then it would only be for a few seconds.
that would only be the case on the coldest days well below 0°.


My 2¢

 

[ARCOgraphite]

Hot , thin oils is when the filter will bypass during on off throttle at mid-high RPM shifts - if you are driving "racy"'.


If the pressure in front of the media is greater than that post media then the filter over-pressure valve will bypass.

On cold, viscous, oil the pressure post media is typically high so the delta may be less here than common sense may bring you to.

Thinl of one door open into Wally-Mart during Black friday and the oil molecules are people.

but - there is an entrance along a sidewalk around back - with a bouncer - if the front door gets jammed.

Now think of scenario where the front door will jam and you will understand the Filter Bypass.

 

[BobsArmory]

As I recall Fram has a filter that crosses to the UPF64R.

 

[StevieC]

Using a lower bypass rated filter will not harm the engine. It's not great if it goes into bypass too often though, because there is unfiltered oil going through the system but it wouldn't be all the time if at all.
Using a filter with a higher than spec'ed bypass rating could be detrimental because it could create oil starvation under certain conditions.

To confirm if the lower bypass filter is a problem you could establish a trend on a UOA and then just change the filter in the equation at the next oil change and see if the trend of wear metals increases substantially to indicate a problem.

How many PSI difference are we talking? 1-2 or like 10? If it's 1-2 PSI I wouldn't worry about it because it's negligible.

 

[goodtimes]

GM uses variable flow oil pumps on some models is the reason I read in their statement on the issue. You don't want the oil pump to go into the wrong flow mode at the wrong time. Thousands of the correct GM filters, made by Champ, are installed every day at GM dealers, just use them unless a company specifically makes the equivalent and you think they are better filters.
Speaking of which, is the Fram Ultra out yet that is supposed to be an equivalent?

 

[SubieRubyRoo]

I've seen a lot more of those "Champ" filters lately with questionable construction, and even tears. Multiply that by the magnitude you just talked about.... no thanks, I'll take a heavier-duty, higher-flow media with a couple psi lower bypass than I will one of those Champs, thank you.

 

[goodtimes]

Don't use the wrong filters or you can damage the engine due to oil pump flow rates. The PF64 has the correct bypass. That's why GM put out the bulletin, and they are the engineers who designed the engines, not some guy on an oil filter forum. Ask your GM dealer.

 

[JoelB]

I believe the proper ultra here is the XG12060 which doesn't exist yet. I saw post about it coming out here but it never seems to have been released. I'll just keep using the UPF64R filters until i can get the proper Ultra. They are decently priced on rockauto and seem to be pretty well built.

 

[ARCOgraphite]

The issue with Subaru turbocharged engines was, older spec 6-9psi-d would bypass and dump sludge into the turbo bearing oil feed screen.

Adding a few mor psi delta into the equation remedied this situation. (21psi-d rating)

Now we have VTEC feed screen and possibly VVT-I feed screen too.

 

[pbm]

I had asked recently about the risk of running a higher bypass pressure filter in my Ford....I'm referring to the PH8316 size in place of the PH400....a reputable BITOGer had said there would be no issue using a filter with a slightly higher bypass setting. (the PH8316 size has approx. a 2 to 4 psi higher bypass depending on manufacturer)

 

[SubieRubyRoo]

Arco, from what I've seen, the EJ25s spec'd a 24# bypass, and the newer FA/FBs call for a 27#, both right in the owner's manuals (and mine was an EJ251 most recently). Where did you get the 6-9psi?

The 3.0/3.3/3.6s are the only engines I know of that were below 24#.

Subaru oil pumps

 

[jongies3]

It's hard to say, aren't majority of FRAMs 12psi? At least the ones for my Tacoma are, and others P/N# I've looked up. I don't know the OEM filter bypass rating for my Toyota so I dunno if it's a thing to worry about or not. Toyota has no flow, bypass, or efficiency ratings for any of their filters that I've been able to find anyway.

 

[Snagglefoot]

Originally Posted by StevieC


How many PSI difference are we talking? 1-2 or like 10? If it's 1-2 PSI I wouldn't worry about it because it's negligible.


In the case of the UPF64R, the difference is 7 to 10 psi.

 

[fdcg27]

Any oil filter listed by the filter maker for this application will be fine.
Since the bypass pressure called for is fairly high, I'd avoid crossing to something that merely fits.
Why these little lo-po engines call for such a high bypass setting IDK, but there is a reason.
OT, but what kind of fuel economy do you see with these little guys in actual use?

 

[carviewsonic]

I would stick with the GM bypass spec filters especially if your cars are still under warranty. Higher bypass filters are available from a few suppliers other than GM, so a bit more choice other than GM only.

 

[JoelB]

I'm getting about 37mpg with mostly in town driving. I've seen 40mpg on a longer highway run. These cars are cheap to buy and cheap to run. Something about that is very satisfying to my brain and my love of efficiency.

 

[ARCOgraphite]

Originally Posted by SubieRubyRoo
Arco, from what I've seen, the EJ25s spec'd a 24# bypass, and the newer FA/FBs call for a 27#, both right in the owner's manuals (and mine was an EJ251 most recently). Where did you get the 6-9psi?

The 3.0/3.3/3.6s are the only engines I know of that were below 24#.

Subaru oil pumps

I go all the way back to the mid 80's Remember the XT Turbo? IIRC they didn't have an overpressure bypass in the FILTER back then it was in the mounting boss - if anywhere.

 

[StevieC]

Originally Posted by Snagglefoot
Originally Posted by StevieC


How many PSI difference are we talking? 1-2 or like 10? If it's 1-2 PSI I wouldn't worry about it because it's negligible.


In the case of the UPF64R, the difference is 7 to 10 psi.

Yeah I wouldn't do it if the difference is that high.