Particle Count Database

It helps to plot the loss of efficiency over the test period, like Davejam did here - it happens to be for the AC Delco data in the table above. There's no doubt that the drop in efficiency has a strong correlation to the dP across the media.
That graph shows efficiency vs time/dirt loading. While it does look to be pretty linear, if you were to plot efficiency vs dP instead, it would look very different, since dP increases exponentially with time/dirt loading.

A filter that sheds a lot of debris as the dP increases will result in a poor ISO 4548-12 efficiency. That's a big reason filters like the Wix XP and Purolator have low ISO efficiency. A very high efficiency like the 3 top filters that Ascent tested can't have an ISO efficiency that high unless they are very low shedders as the dP increases.
The way I see it, all filters are shedders, it's just that the sizes of particles that are prone to shedding will be larger for a lower efficiency filter. For particles similar in size to the filter's absolute micron rating it won't shed much, but around the nominal micron rating size, it will be prone to shedding a lot.

So if you're only looking at particles of a specific size, say 20 micron, a filter like the BOSS will look be a "shedder" at that size, since 20 micron is a small particle for that filter. A more efficient filter should behave similarly, but maybe for particles that are around 10 micron.
 
That graph shows efficiency vs time/dirt loading. While it does look to be pretty linear, if you were to plot efficiency vs dP instead, it would look very different, since dP increases exponentially with time/dirt loading.
Maybe you missed this link because I added it later to my last post - linked again below. You would somehow have to look at how the efficiency decreased with the dP held constant at different dP levels to see that impact on the efficiency loss. The incoming flow debris concentration rate is constant in the ISO test, so it's possible that as the total amount of loading increases in the media, that the shedding rate also increases pretty linearly mainly because the capture rate for any given efficiency filter would also basically be linear. The dP difference between 6 PSI and 14 PSI may not be enough to see any notible affect the shed rate, and it would take much more of a dP difference to make the efficient loss curve non-linear. Bottom like is that debris shedding does increase with the amount of loading, and so does the dP.

Using the raw PC data, one could plot the efficiency loss for the specific particle sizes measured, and have a curve similar to the referenced Purolator/M+H curve shown in the Ascent ISO testing thread.

If an already loaded filter was setup to monitor the shedding particles on the downstream side as clean oil was flowing through it, I would suspect there would be some correlation between the dP across the media vs the level of shedding. I'd think that more flow and dP through the media should break more debris loose from the media.


The way I see it, all filters are shedders, it's just that the sizes of particles that are prone to shedding will be larger for a lower efficiency filter. For particles similar in size to the filter's absolute micron rating it won't shed much, but around the nominal micron rating size, it will be prone to shedding a lot.
That basically just reflects what the ISO 4548-12 shows. That more efficient filters don't shed as much as lower efficiency filter, regardless of the exact mechanism causing the shedding. Those filters simply couldn't rate that high in ISO efficiency if they were a big shedder. As seen in Ascent's ISO testing, all the more efficient filters had much less debris shedding as they loaded up. What's the definition of "nominal", as some think it means different things - did you mean absolute micron rating?

So if you're only looking at particles of a specific size, say 20 micron, a filter like the BOSS will look be a "shedder" at that size, since 20 micron is a small particle for that filter. A more efficient filter should behave similarly, but maybe for particles that are around 10 micron.
When you look at the top 3 filters in Ascent's test, all with pretty high efficiency, they all hold high efficiency down to 15u, so they aren't shedding much of anything down to 15u. The Wix XP and Boss lost efficiency fast, and they shed debris like crazy compared to the 3 efficient filters. It would have been nice to see the curves go down to 5u, and Andrew did say his particle counters could go down to 4u in that thread, but he elected to only measure down to 15u.
 
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That's pretty interesting. It does make me wonder if there can be big differences in how different types of media perform with regards to particle shedding with variable flow.

Just based on the particle count data I have, I have a suspicion that the OG Ultra might perform worse in this regard versus some other filters like the Amsoil/RP, but I think both filters use similar synthetic microfiber media, so, I don't know.
Do you think WIRE BACKED media helps with “shedding” ?
 
You would somehow have to look at how the efficiency decreased with the dP held constant at different dP levels to see that impact on the efficiency loss.
I think the closest we have to this is Ascent's test with the Purolator BOSS (but only at a single dP level). There is virtually no increase in dP in the first 15 minutes of dirt loading, yet the efficiency at 20 um drops from 84% to 63% in that time. Here's the dP chart:

1754347798893.webp


The dP difference between 6 PSI and 14 PSI may not be enough to see any notible affect the shed rate, and it would take much more of a dP difference to make the efficient loss curve non-linear. Bottom like is that debris shedding does increase with the amount of loading, and so does the dP.
Yes, I think it's the dirt loading itself that's the root cause of the drop in efficiency in the ISO tests, not the dP increase. Yet, the pulsation testing you linked to does show a remarkable reduction in efficiency when the flow rate is sharply increased, so dP caused by higher flow can also have a big effect on efficiency when the media is loaded up. I'm guessing that the ISO testing doesn't show the efficiency dropping a lot more as the dP goes exponential because the increase is still pretty gradual and the system is basically never far from a steady state.

That basically just reflects what the ISO 4548-12 shows. That more efficient filters don't shed as much as lower efficiency filter, regardless of the exact mechanism causing the shedding. Those filters simply couldn't rate that high in ISO efficiency if they were a big shedder. As seen in Ascent's ISO testing, all the more efficient filters had much less debris shedding as they loaded up. What's the definition of "nominal", as some think it means different things - did you mean absolute micron rating?
By nominal, I meant an efficiency of ~50%. Basically what I was trying to say is that if a particle is so small that it's filtered at <50% efficiency, it's probably going to get through the filter media if it comes loose, especially since it's likely trapped deep in the media, so it's of a size that's prone to shedding.

A particle large enough to be filtered at 99% efficiency is going to be trapped near the surface of the media, and if it comes loose, it will almost always just become trapped again deeper into the media. So these large particles aren't prone to shedding.

Low- and high-efficiency filters will both be resistant to shedding for large particles, it's just that a "large particle" may be 30+ microns for a filter with low efficiency, but only 15+ microns for a filter with high efficiency.

The most efficient filters in Ascent's testing probably would have shed a lot of >6 um particles at high levels of dirt loading, but we don't really know since particles that small weren't measured. They may have even shed a lot more particles in that size range compared to a low efficiency filter, since they'd be loaded up with a lot more of them.
 
Do you think WIRE BACKED media helps with “shedding” ?
That's a good question. I think that if the filter media is able to deform, either on a macroscopic level or even just the individual fibres shifting around when operating conditions change, that you might expect it to be more likely to shed particles. So, maybe.

In the pulsation testing that @ZeeOSix posted, the metal mesh filter performed really well in variable flow conditions. Is it because the metal mesh media is more rigid than cellulose or fiberglass media and doesn't move around as much?

I think the OG Fram Ultra (the older ultra with full synthetic media) and the Amsoil/Royal Purple are both wire-backed though, no?
 
That's a good question. I think that if the filter media is able to deform, either on a macroscopic level or even just the individual fibres shifting around when operating conditions change, that you might expect it to be more likely to shed particles. So, maybe.

In the pulsation testing that @ZeeOSix posted, the metal mesh filter performed really well in variable flow conditions. Is it because the metal mesh media is more rigid than cellulose or fiberglass media and doesn't move around as much?

I think the OG Fram Ultra (the older ultra with full synthetic media) and the Amsoil/Royal Purple are both wire-backed though, no?
Yes Amsoil/RP (and Endurance) are wire backed.
The “OG” you mention is the old wire backed XG Ultra, but it was never 100% synthetic like the others mentioned.
 
The “OG” you mention is the old wire backed XG Ultra, but it was never 100% synthetic like the others mentioned.
It was at one time, it was dual layered and full synthetic and the media was pink colored. Go read the sticky thread by @OVERKILL at the top of this forum. Fram made different levels of changes to the Ultra over a year or so, and it didn't hit every model at the same time. The one that Ascent tested has pink media, so it probably was the dual layered full synthetic media.

Snapshot from the Ascent video. Royal Purple on the left, Fram OG Ultra on the right.

1754356683300.webp
 
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That's a good question. I think that if the filter media is able to deform, either on a macroscopic level or even just the individual fibres shifting around when operating conditions change, that you might expect it to be more likely to shed particles. So, maybe.

In the pulsation testing that @ZeeOSix posted, the metal mesh filter performed really well in variable flow conditions. Is it because the metal mesh media is more rigid than cellulose or fiberglass media and doesn't move around as much?

I think the OG Fram Ultra (the older ultra with full synthetic media) and the Amsoil/Royal Purple are both wire-backed though, no?
I don't think the wire backing really does anything to keep the fibers in the media from moving any differently from the oil flow. The wire backing on the Ultra (and on the other filters like the RP and Amsoil) is there so the media can retain the shape and spacing of the pleats. Without the wire backing on structurally weak media like that, the oil flow would basically destroy and pleat shaping from flow and the dP forces - the pleats would all probably fold over flat. It might not even be able to retain any real shape at all with oil flow and dP without the wire backing. The media is upstream of the wire backing, and the oil should flow through the media the same before hitting the pretty wide open spacing of the wire backing, so I don't really see how wire backing could change the way the media fibers would react to flow going through the media.
 
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It was at one time, it was dual layered and full synthetic and the media was pink colored
Looks like we’re splitting hairs here, but I found this from Fram:

“Yes, the FRAM Ultra oil filter has undergone design changes over time, and its media composition has evolved

Previously, the FRAM Ultra filter featured a dual-layered synthetic filter media. This included a layer of fully synthetic media that was supported by a metal screen.
More recently, FRAM announced a new and improved Ultra Synthetic oil filter featuring a redesigned 2-ply media. According to FRAM, this new design eliminates the metal screen and incorporates a synthetic blend layer for durable structure and filtering support, alongside a fully synthetic media layer for higher flow efficiency and superior filtration.
>>>NOTE>>>>
“Therefore, while the Ultra filter may not have always been entirely 100% synthetic across both layers, it has consistently incorporated a fully synthetic media layer within its design. “
 
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Looks like we’re splitting hairs here, but I found this from Fram:

“Yes, the FRAM Ultra oil filter has undergone design changes over time, and its media composition has evolved

Previously, the FRAM Ultra filter featured a dual-layered synthetic filter media. This included a layer of fully synthetic media that was supported by a metal screen.
More recently, FRAM announced a new and improved Ultra Synthetic oil filter featuring a redesigned 2-ply media. According to FRAM, this new design eliminates the metal screen and incorporates a synthetic blend layer for durable structure and filtering support, alongside a fully synthetic media layer for higher flow efficiency and superior filtration.
>>>NOTE>>>>
“Therefore, while the Ultra filter may not have always been entirely 100% synthetic across both layers, it has consistently incorporated a fully synthetic media layer within its design. “
I don't think so, it's pretty simple:

- The OG Ultra (and XtendedGuard that proceeded it) had two distinct layers of pink fully synthetic media with wire backing.
- The updated Ultra (non-OG) that came after, did away with the wire backing, instead opting for a blend media backing layer, faced with a full synthetic "topper" layer.

This was a cost-saving measure.

I wouldn't trust First Brands to know a bloody thing about the product. Back, long before they were involved, when Jay (Motorking), who was the Technical Directory at FRAM, was involved on this forum, he stated quite clearly that the OG Ultra was as I described. If you'd like me to dig up the posts, I can do so, or, you can search his posts on here and find it yourself.

Edit, quote from Jay:
Motorking said:
Amsoil filters are made by Champion Labs, Not Fram. Yes, they use the same tapping plate and bypass valves in many filters as FRAM does in Ultra. That is because FRAM and Champ used to be a joint operating business. That ceased May 2016. The Fram Ultra is a two layer synthetic media, Amsoil is single layer synthetic media. As the supply of tapping plates at Champ gets used up, you may see the Amsoil filter change.
FRAM today only makes filters for Honda, Subaru, Polaris, Motomaster, and FRAM

Motorking said:
FRAM Ultra has great efficiency (99%@20 microns). Huge capacity (new box released in March will show 20k change intervals). Silicone adbv, the only dual layer synthetic media filter in the market, all other brands with syn media are single layer. Pleated wire backed media, not plastic like others.

There's a thread where he goes into the details about the media, I'm sure you can find it if you search.
 
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