Oil Filter Efficiency for Cleaner Oil

ZKWBQD said:

It can be difficult getting the oil filter you want. In the event of an engine failure GM will do everything possible to deny warranty coverage. That's why so many people will only have the oil changed at the dealer. The dealer is unlikely to use the filter that you like. The one thing that I do is I change my oil every 3,000 miles. But I do it at the dealer.

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I work next to a guy that has one of the brand new full size chevy trucks with the 4cyl. he loves it and says it tows 90% as well as his diesel which running 87. and way better than any gas v8 he's owned. direct injection and turbo doing work. they sold him a maintenance free package when I got it, all he's gotta do is go in and everything is done free for I think 2 years? anyways, they won't do it at the mileage he wants, no 3k oil changes for him, they will only do it at the manual recommend times.

now he doesn't have afm or anything and it probably won't matter. but still, no only is the dealer not going to use your parts, they might not even be willing to change when you want them too. the original owner won't care, cause people like that don't keep their trucks for 200k but the next 2 owners might.

j91z28d1 said:

I work next to a guy that has one of the brand new full size chevy trucks with the 4cyl. he loves it and says it tows 90% as well as his diesel which running 87. and way better than any gas v8 he's owned. direct injection and turbo doing work. they sold him a maintenance free package when I got it, all he's gotta do is go in and everything is done free for I think 2 years? anyways, they won't do it at the mileage he wants, no 3k oil changes for him, they will only do it at the manual recommend times.

now he doesn't have afm or anything and it probably won't matter. but still, no only is the dealer not going to use your parts, they might not even be willing to change when you want them too. the original owner won't care, cause people like that don't keep their trucks for 200k but the next 2 owners might.

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I rented a Sierra with the 2.7T gasser in February for a week in Lake Tahoe. I loved it! I would have no hesitation at all about owning one tow our 7500 lb. camper with.

Geotrash said:

I rented a Sierra with the 2.7T gasser in February for a week in Lake Tahoe. I loved it! I would have no hesitation at all about owning one tow our 7500 lb. camper with.

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crazy right.

and they can't sell them because truck = v8 or nothing crowd while idling around town its whole life till it eats its lifters

I run the best filter of course! The K&N Gold, the one with the 1" nut on the end to aid in removal, HP-2011, the long one. 10-12 microns at 99% and flows 16 gallons per minute or 960 gallons per hour. Nobody else comes close. $15-18 a pop, ain't cheap but then the best never is.

donjetman said:

Let's say you want cleaner oil for whatever reason. You could change your oil often, or use a more efficient oil filter and change it less often.

The Fram Ultra 99.8% efficiency @ 15 microns

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The top Fram filter is definitely a good choice. Supposedly ?? the Ultimate (today) is basically the equivalent of the 'Ultra' used in this test.

An important thing to note is that higher efficiency doesn't necessarily mean long lasting oil filter.


As shown in the graph here, the Fram Ultra lasts for 13.6 grams, while the Wix XP holds on for 18.1 grams. The way the test works, approximately .42 to .44 grams of particles are injected every minute. The test is stopped when the differential pressure increases a set amount.

If you do the math:
Fram Ultra ~= 13.6g / 32 min = .425 g/min
Wix XP ~= 18.1g / 43 min = .421 g/min

In other words, they are virtually collecting the same amount within the precision of measurement, but the Wix actually collects 33% more, or more specifically collects nearly all of the injected particles for 33% longer interval.

donjetman said:

Oil filters that are rated at less than 62% at 20 microns (aka rock catchers):
Wix XP
NAPA Platinum

The test for oil filters is ISO 4548-12

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To address the multi-pass efficiency of the test:

The way the test works, particles are injected at different sizes roughly by weight, such that the smaller particles are represented at an exponential distribution for the smaller sizes. The particles are injected at a steady rate and the test continues until the differential pressure rises indicating a loss of filter capacity.

So let's say for the sake of argument that the filter is capable of filtering 400 20 micron particles every 5 minutes. If you inject 100 particles per minute (500 per 5 minutes), after 5 minutes, you have 500 measured before the filter and 100 after. That is considered an 80% efficiency. If you continue the test for 40 minutes, you have filtered 400 x 40/5 = 3200 particles, but you have 100 that escaped every 5 minutes, so that is 800. If you add 800 to the 500 you injected in the last five minutes, the ratio of 400 that you captured to the 800 escaped plus the new 500, you are only 400/1300 = 30% efficient.

So the longer you can continue to filter without causing blockage, the more the escaped particles count against you for multi-pass efficiency. The reality however is that you have captured 3200 particles, which in my mind is 3200/4000 (captured vs injected) or 80%, but that is not how the test is actually measured, because it is purely particles counted before and after at an instant in time, not relative to what is actually captured over time. And of course being able to capture MORE particles for a longer duration of time actually counts against you.

The ideal would be to have high flow, low resistance, high capacity and high filtration in a very short interval, but it is hard to do that, so there are compromises. You can have the ability to supposedly capture 6000 miles of heavy use in a 30 minute window, or you can capture 9000 miles of heavy use in a 45 minute window. The ideal is probably more of a multistage filter where you always filter the large particles and you bypass a small percentage of flow to filter the very small particles without interrupting the flow or dropping the pressure.

With a really good filtration system, I think you could turn a 400k mile engine into a 600k mile one, but the reality is that most of the oil related failures before 200k have much more to do with a lowered oil pressure, and almost nothing to do (and I would say unproven) with a sub 98% 20 micron efficiency for the oil filter.

I think I'll have to reread that again to fully understand what you're saying. but my question is how are particle bigger than the filter rating getting thru the media? is it some kinda break thru or just the bypass valve? if so it seems a higher bypass valve pressure would be helpful?

on a side note, here's a wix filter without a bypass valve with ratings I don't fully understand listed on the side of it. might be interesting.

j91z28d1 said:

I work next to a guy that has one of the brand new full size chevy trucks with the 4cyl.

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j91z28d1 said:

...now he doesn't have afm or anything

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It actually does have AFM.

Let's say I use a PF 66 GM filter, I would like to use a larger longer filter in its place, but I don't understand how to figure out what is a bigger filter that would fit that same filter base, is this easy to figure out?

j91z28d1 said:

on a side note, here's a wix filter without a bypass valve with ratings I don't fully understand listed on the side of it. might be interesting.

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I believe that is a fuel filter. Maybe it could be adapted to be a little bypass filter? I run the large Amsoil EaBP90 bypass filter.

It is my understanding in the real world there has to be something terribly wrong with an engine or its oil for athe full flow oil filter to go into bypass. Normally there is very little differential pressure across the media in a oil filter.