Reasoning as to why extended OCI oil filters might need better micron ratings than normal filters?

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I was thinking about why my OEM Toyota filters, which are not designed to be used for crazy long OCI of 10K+ miles, have poorer filtering efficiency for smaller particles than the filters used for 15-20K intervals.

I'm clearly no oil expert, so please go easy on me if my theory is completely out of whack. LOL

The motor oil itself can suspend quite a large volume of particles without those particles damaging parts as long as they are below a certain size. My OEM filter can remove those larger particles and ignore the smaller ones, as long as the oil is never left too long to be fully loaded beyond its limit with smaller particles. If the oil is changed soon enough, those tiny particles never accumulated enough to cause engine harm, beyond just normal wear and tear.

If the oil is allowed to accumulate too many small particles, beyond what it can keep suspended, then they may increase engine wear.

For doing long OCI, the filter must take up some of the duty of keeping those small particles from loading the oil too soon before the oil change. Thus, the extended OCI filters having a much higher efficiency on smaller particles compared to cheaper/normal oil filters.

Would this explain why so many people who used the cheapest or average oil filters, along with normal/cheap oil, but doing so at shorter change intervals, can have engines that last 500K+ miles without any major rebuild of parts that would tend to wear out?

Then, would it also be right to say that for normal OCI, within OEM specs, one wouldn't be gaining any extra engine protection by using a high efficiency oil filter? Maybe even less protection if the flow rate and bypass specs are too far off from OEM spec on OEM filters?

My Toyota Denso-made oil filters I now use on 2 rigs, are considered to some of the "worst" in terms of micro efficiency, yet we all know, Toyota doesn't mess around when it comes to making their engines run for a long time. Did the engineers understand that filter efficiency below a certain threshold, using non-extended OCI, is a worthwhile tradeoff in order to have a filter that is less likely to go into bypass mode?

Please, let me know how wrong I am, which is probably all of it. But, I have been reading BITOG for years now, and this seems to be the general way these things work, right?
 
I was thinking about why my OEM Toyota filters, which are not designed to be used for crazy long OCI of 10K+ miles, have poorer filtering efficiency for smaller particles than the filters used for 15-20K intervals.

I'm clearly no oil expert, so please go easy on me if my theory is completely out of whack. LOL

The motor oil itself can suspend quite a large volume of particles without those particles damaging parts as long as they are below a certain size. My OEM filter can remove those larger particles and ignore the smaller ones, as long as the oil is never left too long to be fully loaded beyond its limit with smaller particles. If the oil is changed soon enough, those tiny particles never accumulated enough to cause engine harm, beyond just normal wear and tear.

If the oil is allowed to accumulate too many small particles, beyond what it can keep suspended, then they may increase engine wear.

For doing long OCI, the filter must take up some of the duty of keeping those small particles from loading the oil too soon before the oil change. Thus, the extended OCI filters having a much higher efficiency on smaller particles compared to cheaper/normal oil filters.

Would this explain why so many people who used the cheapest or average oil filters, along with normal/cheap oil, but doing so at shorter change intervals, can have engines that last 500K+ miles without any major rebuild of parts that would tend to wear out?

Then, would it also be right to say that for normal OCI, within OEM specs, one wouldn't be gaining any extra engine protection by using a high efficiency oil filter? Maybe even less protection if the flow rate and bypass specs are too far off from OEM spec on OEM filters?

My Toyota Denso-made oil filters I now use on 2 rigs, are considered to some of the "worst" in terms of micro efficiency, yet we all know, Toyota doesn't mess around when it comes to making their engines run for a long time. Did the engineers understand that filter efficiency below a certain threshold, using non-extended OCI, is a worthwhile tradeoff in order to have a filter that is less likely to go into bypass mode?

Please, let me know how wrong I am, which is probably all of it. But, I have been reading BITOG for years now, and this seems to be the general way these things work, right?
Not a fan of xtended OCIs, but Toyota's filters are made for 10K mile OCI, if you want to get a "Better" filter get the Toyota TRD filters. but you're going from a ca$ 6 to ca$ 21 each (US prices probably lower)
 
I thought Toyota now recommends 10K OCIs for non-severe service. I'd say that's in the realm of a long OCI. Many engine wear studies show that it's the smaller particles below 20u that actually cause most of the wear. Maybe Toyota has increased their filter efficiency as they have increased their OCI ... that would be the logical thing to do IMO. It's been a long time since any ISO efficiency test was seen on a Toyota filter.

When going with a longer OCI, then a higher efficiency oil filter should help keep the overall oil contamination level of the sump lower. Think of engine wear due to particles in the oil as the contamination level of the sump times how many times that sump volume gets pumped through the engine. You can either shorten the OCI, or increase the filter efficiency to help keep the sump contamination level down as the OCI increases.
 
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Then, would it also be right to say that for normal OCI, within OEM specs, one wouldn't be gaining any extra engine protection by using a high efficiency oil filter? Maybe even less protection if the flow rate and bypass specs are too far off from OEM spec on OEM filters?

If you've been following the thread linked below, I'd say the Toyota OEM (or any OEM for that matter) is not going to flow any better (probably worse) as these high efficiency aftermarket filters.

 
So, if it does indeed help to use a high efficiency filter for OEM-spec OCI, is there any data to help suggest that the engine sees any meaningful reduction in wear over say, a 300k+ mile life of the engine? Only in terms of parts wearing out from friction, not all other factors that have nothing to do with oil. With the number of vehicles that have gone over 500K miles on the original engine with no major rebuilds, using normal filters, I find it kind of hard to believe that a extended drain interval filter with higher efficiency would help much unless one chooses to go longer, using the appropriate oil of course. Or would we see those engines go from 500K before dying from wear, to 550K+ or whatever if a more efficient fitler is used for normal OCI?
 
So, if it does indeed help to use a high efficiency filter for OEM-spec OCI, is there any data to help suggest that the engine sees any meaningful reduction in wear over say, a 300k+ mile life of the engine? Only in terms of parts wearing out from friction, not all other factors that have nothing to do with oil. With the number of vehicles that have gone over 500K miles on the original engine with no major rebuilds, using normal filters, I find it kind of hard to believe that a extended drain interval filter with higher efficiency would help much unless one chooses to go longer, using the appropriate oil of course. Or would we see those engines go from 500K before dying from wear, to 550K+ or whatever if a more efficient fitler is used for normal OCI?
Where are you seeing those?
 
If doing 3-5K OCIs, you don't need as good of an oil filter as doing 10~12K OCIs ... as an example. You would be keeping the sump contamination level under control by dumping the sump and using new oil when doing short OCIs.

Who knows how often the OCIs were conducted on these 500K mile engines. One thing that can't ever be proven with any valid test data is that dirtier oil is just as good or better than cleaner oil ... regardless of how long the oil is used. There are dozens of papers showing that cleaner oil always results in less wear. It's just up to each person to decide what they want to do in terms of keeping the oil clean as possible (and using the right oil viscosity for the conditions) if they are worried about engine wear.
 
Where are you seeing those?
Lots of old Volvo and Mercedes and Toyota and Honda and Domestic v8 vehicles get into that range. What does "lots" mean? I don't know, but there are plenty of rigs hitting high numbers out there.

What have you been using on your Sienna, which is pushing 500K? Do you think the choice of oil or filter got it to that point, or just good overall care and regular maintenance?

My Toyota pickup with the 2.4 22RE motor is pushing into the 350K range right now, and it hasn't seen the best life being used for some heavy duty work and neglect from high school and college years. Always used cheap filters and conventional oil and often pushed the OCI a bit further than I should have. Last time the engine was apart for a separate issue than wear, the mechanic said everything was looking really good with nothing standing out as being overly worn. No bottom end problems and the top end only showed the miles based on the varnish.
 
I think the consensus from the engineers standpoint is the air filter matters more than worrying about the oil filter. OEM air filters tend to be of high quality.
Consensus from an engineer is not needed. I was sent out to service one of the companies long term rentals. The service manager gave me all the filters. The old air filter was packed solid with dirt. The new filter was the wrong application and was about 2 inches to short so it didn't seal or filter.. I called in to have him bring me a proper filter ,the manager got defensive called me all sorts of names , being the kind and loving person I am I put the filter in, with in a month I was sent out to check on the engine smoking. Yes it was, It needed the engine rebuilt, a Perkins Diesel Engine is expensive. The shop guys rebuilt the engine and replaced the Air filter again with the wrong filter. A month later I was sent out because the engine was smoking again. Back into the shop for a rebuild. This time I told the shop guy that he put the wrong Air filter in it. After another engine rebuild and the proper air filter that went to the end of the air filter housing "A Donaldson air filter" the engine lasted through the lease which was 3 years and remained in the short term rental fleet for a while. An air filter is the most important filter.
 
Lots of extended service oil filters (rated for 15K to 20K miles) are high efficiency thanks to full synthetic media. And their holding capacity is high also in order to be rated for that higher use mileage.
 
The 500k engines are few and far between.... Driving style and change intervals will be bigger determinants than oil/filters used.

I would use the best filter you can afford for your interval and change it at every interval.

Automakers don't care how long your engine lasts after the warranty expires. Do you? The automaker isn't looking out for you. The class action lawyers are!

A filter in bypass still has the oil flow thru the media until its completely clogged. Only the remainder of flow, that can't make it thru the media, goes thru the bypass.

Can't compare an ol' engine with newer ones. My 400 Ford went bazillion miles and made less power than my 1.4T VW. A 2.3-2.5T can make 250-300hp when compared to a 22RE making ~100hp.

Toyota does mess around. Plenty of their engines have issues. Maintain it well and you might prevent a few.

Its the owner, that takes care of his engine, and maintains it well, and doesn't abuse it.... that determines whether the engine lasts or not.

Engineers are usually bossed around by non-engineers. Cost accountants and marketing determines more than engineers.
 
There is one data point from Amsoil, a competitor, ten years ago, based one one test of one Toyota oil filter, to make the claim they don’t filter efficiently. It is repeated over and over and we see now it is believed. I don’t believe it at all, not that gullible. And it’s old. There have been particle count tests on actual oil samples used in cars here, no full flow filter is doing that well I can see. Toyota filters have a lot of media so if you go the miles as they say under the conditions they say, you won’t have issues with the filter. I wouldn’t worry about it, the car came new with a Toyota filter. Lexus comes new with the same filters. Every day thousands of Denso filters are installed at the dealerships nationwide.
 
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There is one data point from Amsoil, a competitor, ten years ago, based one one test of one Toyota oil filter, to make the claim they don’t filter efficiently. It is repeated over and over and we see now it is believed. I don’t believe it at all, not that gullible.
You could pay @Ascent Filtration Testing to test a Toyota OEM for ISO 4548-12 efficiency if you don't believe the old data.
 
Automakers don't care how long your engine lasts after the warranty expires. Do you? The automaker isn't looking out for you. The class action lawyers are!

A filter in bypass still has the oil flow thru the media until its completely clogged. Only the remainder of flow, that can't make it thru the media, goes thru the bypass.

Toyota does mess around. Plenty of their engines have issues. Maintain it well and you might prevent a few.
I don't know... I think the old trope of car makers not caring once past the warranty might only apply to shady outfits like Dodge. Toyota clearly has engineered their vehicles to go much longer than the warranty period. It's part of why so many Toyota owners are Toyota owners for life. Making cruddy vehicles that fall apart after 100K can often result in the owner swearing off the brand for good. Seeing how big Toyota is and how well-made their products are, I think it works out pretty well for them. Balances out the fact that those people might not buy a new car as often with which brand they choose when they do buy a new one. In Japan, people don't keep their vehicles very long at all compared to North Americans, often under 100K if I remember correctly. Yet they still have some of the longest lasting vehicles on the road made in Japan and sold into other markets new or used.
 
You could pay @Ascent Filtration Testing to test a Toyota OEM for ISO 4548-12 efficiency if you don't believe the old data.
I could, but would rather give the money to The American Cancer Society.
Thinking more about this, why do I have to provide proof against Amsoil’s claim? Remember around here that isn’t how it’s done. They at least should have the original lab reports,like a Blackstone report, not their own blurb, which is second hand information. Anyone can say whatever they want, not first hand information. They need to test many filters and sizes, like Fram. Not as trustworthy.
 
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wonder if those shady outfits use 50 micron filters …
have to do something like that to keep shady status
 
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