New Kubota 4 Micron filter

The original fram titanium was filtering as efficiently as 5 to 10 microns depending on which beta ratios you want to look at.
All oil filters have some efficiency (beta ratio) at 5 and 10 microns. But what is it? That's probably why Harley calls their oil filter a "5 Micron" oil filter (for marketing purposes), just because it can capture some 5u particles. It might only be 10% or 20% efficient at 5u, but it catches a small percentage of some 5u particles so it must be a "5 Micron" filter.

The fram synthetic endurance is supposed to be about 12 microns as long as it doesn't leak.
12u at what efficiency?
 
4 microns at what efficiency? That's what counts, not just a statement that it's a "4 micron" filter. Harley plays that game with their "5 micron" oil filter. Every oil filter will catch some amount of 4 micron particles. But is that at 2%, 25% or 50% or ??%.

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Wonder what that asterisk by the word "efficiency" points to? Probably says "Right before the filter it totally clogged". 😄
Take good care of your equipment with Kubota Genuine oil filters. Precisely matched to your machine. To keep it running right.

*Oil filter efficiency on a Kubota genuine oil filter (4-micron filtration) measured by Kubota using ISO 19438 (JIS D1623).
 
I’m going out on a limb here and saying Kubota fuel filters are 4 microns using the ISO 19438 test. Oil filters are tested using ISO 4548-12.

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Yeah, that seems strange if they weren't testing fuel filters with something besides the ISO 19438 they referenced. And ISO 19438 isn't meant to efficiency test oil filters, so no company with any real knowledge of filter testing would use ISO 19438 to test oil filters.

Right in the "Introduction" section of ISO 19438 it says:
"This document establishes a standard test procedure for measuring the filtration efficiency, retention capacities and resistance to flow of fuel filters."

Having a fuel filter that is 99.5% @ 4u makes more sense than an engine oil filter being that efficient, which even no big filter company makes that efficient that I've ever seen claimed.
 
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So Kubota is testing oil filters using an ISO fuel filter test?
I doubt that ... more like not knowing how to advertise their filters correctly. No spin-on engine oil filter is 99.5% @ 4u. Fuel filers are typically that efficient however.
 
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All oil filters have some efficiency (beta ratio) at 5 and 10 microns. But what is it? That's probably why Harley calls their oil filter a "5 Micron" oil filter (for marketing purposes), just because it can capture some 5u particles. It might only be 10% or 20% efficient at 5u, but it catches a small percentage of some 5u particles so it must be a "5 Micron" filter.


12u at what efficiency?
If it's a fuel or hydraulic filter then it should be rated beta 75 or higher.
So chances are a 25 micron hydraulic filter is way more efficient than a 20 micron engine oil filter. As the oil filter is probably being rated by it's beta 2 numbers and the hydraulic filter they're completely opposite, looking like they could be rated anything from beta 20 to 75 if you're wix and beta 1000 if your Donaldson. Both vary wildly from manufacturer to manufacturer which microns they claim their filters are rated for.

The betas for the synthetic endurance were pretty good something like beta 75 for 20 micron, pretty much wipes nearly all 20 micron dirt compared to a typical engine oil filter. And then for the traditional beta 2 or "normal rating" its an unusually small 12 microns. More like a decent hydraulic filter. If they're not leaking internally.
Not as good as the old fram titanium.
 
If it's a fuel or hydraulic filter then it should be rated beta 75 or higher.
So chances are a 25 micron hydraulic filter is way more efficient than a 20 micron engine oil filter. As the oil filter is probably being rated by it's beta 2 numbers and the hydraulic filter they're completely opposite, looking like they could be rated anything from beta 20 to 75 if you're wix and beta 1000 if your Donaldson. Both vary wildly from manufacturer to manufacturer which microns they claim their filters are rated for.
Beta 75 is 98.7%, which is considered the "Absolute Efficiency" in the fluid filter world. So beta 75 at what particle size? Saying "a 25 micron hydraulic filter is way more efficient than a 20 micron engine oil filter" doesn't mean much without corresponding beta ratio or efficiency that those micron sizes are at. Only time throwing out just a beta ratio would make sense is if the particle size as assumed to be say 20u that would correlate to the beta ratio or efficiency being discussed.

When you talk about filter efficiency and beta ratio, you need to stipulate at what particle size or it doesn't have any real meaning.

The betas for the synthetic endurance were pretty good something like beta 75 for 20 micron, pretty much wipes nearly all 20 micron dirt compared to a typical engine oil filter. And then for the traditional beta 2 or "normal rating" its an unusually small 12 microns. More like a decent hydraulic filter. If they're not leaking internally.
Not as good as the old fram titanium.
The Fram Endurance is shown at "99%+ for particles greater than 20u" (which basically means at 20u and greater particles) on Fram's website ... so it would actually be better than beta 75 at 20u - if not leaking internally.

FYI, beta 2 is not "normal" efficiency, but "nominal" efficiency (aka 50% efficiency). I'd say the Fram Endurance would be more like 85-90% efficient at 12u based on the Ascent ISO efficiency data on the Royal Purple [ LINK } which is basally a Fram Endurance in a different can (both made by Champion Labs). And yes, that's if it's not leaking internally with a ruffled leaf spring stamping. The Royal Purple came in just a hair below the OG Ultra in Ascent's test ... but the Royal Purple never used a leaf spring gasket like the OG Ultra, so even if it had a smooth leaf spring, it's still possible to have a very slight leak at the metal-to-metal seal with could drop the efficiency a hair below the OG Ultra in Ascent's efficiency test. Whoever designed the OG Ultra was going for max efficiency by using a gasket on the leaf spring.
 
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Beta 75 is 98.7%, which is considered the "Absolute Efficiency" in the fluid filter world. So beta 75 at what particle size? Saying "a 25 micron hydraulic filter is way more efficient than a 20 micron engine oil filter" doesn't mean much without corresponding beta ratio or efficiency that those micron sizes are at. Only time throwing out just a beta ratio would make sense is if the particle size as assumed to be say 20u that would correlate to the beta ratio or efficiency being discussed.

When you talk about filter efficiency and beta ratio, you need to stipulate at what particle size or it doesn't have any real meaning.


The Fram Endurance is shown at "99%+ for particles greater than 20u" (which basically means at 20u and greater particles) on Fram's website ... so it would actually be better than beta 75 at 20u - if not leaking internally.

FYI, beta 2 is not "normal" efficiency, but "nominal" efficiency (aka 50% efficiency). I'd say the Fram Endurance would be more like 85-90% efficient at 12u based on the Ascent ISO efficiency data on the Royal Purple [ LINK } which is basally a Fram Endurance in a different can (both made by Champion Labs). And yes, that's if it's not leaking internally with a ruffled leaf spring stamping. The Royal Purple came in just a hair below the OG Ultra in Ascent's test ... but the Royal Purple never used a leaf spring gasket like the OG Ultra, so even if it had a smooth leaf spring, it's still possible to have a very slight leak at the metal-to-metal seal with could drop the efficiency a hair below the OG Ultra in Ascent's efficiency test. Whoever designed the OG Ultra was going for max efficiency by using a gasket on the leaf spring.
Sounds like they're a lot better than even a typical hydraulic filter.
So they're more like at least beta 100 for 20 micron and around beta10 for 12 micron.
Sounds like they just need to go back to putting a 3 cent gasket on the bypass.
 
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