How long before a filter goes to bypass?

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I was speaking with an owner from a oil change shop who stated that most oil filters start to bypass at approx. 4,000 miles due to clogged filter media. I understand that he has an obvious bias and his statement was a broad generalization when in fact, there are many variables that come in to play. However, in general terms, how long should a filter be used?
Secondly, do manufacturers take oil filter life into account when determing the length of OCI's?
Thank you.
 
Yes, manufacturers take into account filter life and plugging when they specify oil change intervals. Honda currently recommends changing the filter every second oil change.

A filter might be in bypass when you first start the engine with cold thick oil.

Once the oil fully heats up it would have to be severely plugged to still be in bypass.

I have run filters out to 20,000 plus km and the media is black but not plugged to the point where I would be concerned about bypassing. As the media starts to fill and plug the filter efficiency actually rises.

Also, you can typically cross reference a longer filter for many vehicles. For example, I am running a TG3600 filter on my Toyota which is about 1 1/2" longer and has significantly more media than the recommended TG3614.
 
It is a good question but many variables make it hard to answer specifically. If we take a well maintained engine and a properly working filter (no defects), the size of the filter matters because more media more dirt it should hold, thus extending life. Bottom line is your filter should be purchased with the amount of time your expected OCI will be. So if you go to Your auto store and buy the premium oil/filter special it should get you through the whole OCI. So GENERALLY you get what you pay for. If you buy a Bosch Distance Plus, you should get an easy 10K. If you buy a $2 Pronto I would lessen my expectations. Also as Christobal said, you can buy cheap filters and change them out at 3-4K. Tough one, bottom line is don't be cheap with filters and if you are going to be, expect to change sooner.
 
I'd think there's a time during a vehicles life too, where the filter would be less-susceptable to dirt/filling up.

Obviously, during break-in on a newer engine, I'd think you'd see more wear, as the parts all start to "seat" properly.

But yea, all would depend on your filter, and the vehicle really, how long it takes before it gets completely clogged, and thus thrown into "bypass" mode....


On a side note; the Hayne's manual for my 88 Dodge Aries recommends changing the oil filter every-other oil change....:) So, I can't see the whole "clogged filter" excuses being that big of a deal.

But of course, this edition was written back in 1992 if I recall....we all know now you may as well just change out the filter when you change the oil, since you gotta go under the car anyways....

and actually, not even :p Mine is easily do-able from the top end hehe, just a matter of getting a small drain pan down there between the radiator hose(s).....so it doesn't leak all down the front of the engine when the filter is removed.

Sure, it'll make it easier removing it from underneath, but not totally mandatory.
 
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It would take a lot of crud to make a filter go into bypass. I have cut M1 filters apart with 15K on them using M1 5-30EP and they were very clean. Also XM says no special filter is required for their EP oils going 15K. Now of course that would be for engines that were clean to start with.
 
I didn't cut open any spin on filter, but I did look at the E430 cartridge paper filter after 13-14k miles and found nothing on the media to suggest that it may be in bypass for clogged media.
 
Originally Posted By: mva
I have run filters out to 20,000 plus km and the media is black but not plugged to the point where I would be concerned about bypassing.


Not to be argumentative, but how do you determine that the media is "...not plugged..."?

I've visually examined various filter media for over 50 years and I cannot distinguish between media with 5k or 15k miles of service.
 
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This ISO test method would tell the whole story. Anyone here have an actual full blown copy of the test standard? It cost big bucks to download it from the internet.

ISO 4548-12:2000
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Methods of test for full-flow lubricating oil filters for internal combustion engines -- Part 12: Filtration efficiency using particle counting, and contaminant retention capacity.

This part of ISO 4548 specifies a multi-pass filtration test with continuous contaminant injection and using the online particle counting method for evaluating the performance of full-flow lubricating oil filters for internal combustion engines.

The test procedure determines the contaminant capacity of a filter, its particulate removal characteristics and differential pressure.

This test is intended for application to filter elements having a rated flow between 4 l/min and 600 l/min and with an efficiency of less than 99 % at a particle size greater than 10 microns.
 
It would take an extremely saturated filter to be in bypass all the time. What would occur is that it would have elevated differential pressure longer as the oil thinned.

Yes, engine man's take everything into consideration, that's why non OLM (includes even less articulate systems) equipped vehicles give a time/mileage recommendation. This allows the "every other" filter change IF mileage is used (for some man's over some years +/-)

So, 15k/year ..lots of hollow miles out of fuel enrichment ..hardly any filter loading going on.

Oddly ..some get this wrong ..but not with filters. Let's say it's 7500/6months ..some forget the "whichever comes first" and just say that they're using the mileage method ..even if it takes 7-8-9 months to accumulate.
 
The filter goes into bypass the very first time you start it with a new filter and new cold oil.

As to when the filter is so clogged that it bypasses with normal hot oil, it will be a very long time. Oil analysis tests for insolubles (and an extra cost test for particulates is available) and these do not show higher quantities unless there is a specific problem with the engine or the environment. I run my filters 10,000 miles with good tests and great engine wear results...112,000 miles on my Tundra and 190,000 on my turbo Volvo, and both are tight and strong with excellent annual oil analyses.
 
Originally Posted By: Ken2
The filter goes into bypass the very first time you start it with a new filter and new cold oil.


I doubt that unless you started the engine with the gas pedal to the floor. The oil pump isn't putting enough oil volume out at idle to make a new filter go into bypass unless the oil viscosity was like honey.
 
Originally Posted By: Hallmark
Originally Posted By: mva
I have run filters out to 20,000 plus km and the media is black but not plugged to the point where I would be concerned about bypassing.


Not to be argumentative, but how do you determine that the media is "...not plugged..."?

I've visually examined various filter media for over 50 years and I cannot distinguish between media with 5k or 15k miles of service.


We're talking about a lot of visable sludge in a filter from a very dirty engine.
 
Originally Posted By: tig1
Also XM says no special filter is required for their EP oils going 15K.


Only because they don't offer a "mid-tier" filter..... just the M1 filters only.
 
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