Purolator One vs Purolator Boss Questions

I don't think the Baldwin has a leaf spring, so maybe it's not a leaker. BR is the last source I'd choose a filter based on efficiency claim, maybe only if there was no other ISO 4548-12 efficiency info on the filter, like the Denso Toyota filters.
Baldwin has a coil spring. No leaf spring. I say that based on Baldwin specs and filter disection videos I've seen. Every source I've ever seen is impressed with Baldwin's build quality.

The Baldwin filters my car can use are rated as 18 microns nominal, which I used to think was good because its better than Wix 21 microns. On the West Coast, and probably the West in general, Wix is king and sets the bar for most people here. I now think that's mostly due to clever marketing at autostores more so than actual filtration performance.

Purolator One (P1) filters much more efficiently than Wix or Baldwin. All 3 flow well. P1 costs much less than W or B in my area.

A P1 seems like an excellent (and cost effective) choice for use on paved roads. Please correct me if I'm wrong.

My only concern with P1 is that I sometimes drive on gravel roads. Gravel can fly up and hit the oil filter can. A P1 can is thinner than W and much thinner than B. A W can is tough and unlikely to burst or be punctured by flying gravel. A Baldwin can is extremely tough and nearly indestructable.

Tough cans to survive driving on gravel roads might partially explain why W & B are so popular in rural areas in the West (and maybe rural places elsewhere). Also it might be that a lot of rural folks (me included - prior to this thread) don't understand filtration efficiency well enough and rely too much on advice from local autostores.
 
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The Baldwin filters my car can use are rated as 18 microns nominal, which I used to think was good because its better than Wix 21 microns. On the West Coast, and probably the West in general, Wix is king and sets the bar for most people here. I now think that's more due to clever marketing than performance.
Most people don't know what "nominal efficiency" really is, so when they see just the micron size related to the nominal efficiency they don't have the whole story. A filter with nominal efficiency at 21u, which is 50% @ 21u, is going to be around 99% at 35u to 40u.

My only concern with P1 is that I sometimes drive on gravel roads. Gravel can fly up and hit the oil filter can. A P1 can is thinner than Wix and much thinner than Baldwin. A Wix can is tough and unlikely to burst or be punctured by flying gravel. A Baldwin can is extremely tough and pretty much indestructable.
Maybe consider the Fram Endurance ... the can on that seems thicker than most in its class. Or even a Fram Racing filter ... those have a really thick can, and I think they are around 95-97% @ 20u.
 
Just another OG Ultra .. so they both showed similar low particle counts. Same with the to MG (MicrGaurd) filers ... they both had similar particle counts between them.
What does the OG mean? What brand is an OG Ultra?

MG is Microguard? Is Microguard the Oreilly house brand filter?
 
Most people don't know what "nominal efficiency" really is, so when they see just the micron size related to the nominal efficiency they don't have the whole story. A filter with nominal efficiency at 21u, which is 50% @ 21u, is going to be around 99% at 35u to 40u.


Maybe consider the Fram Endurance ... the can on that seems thicker than most in its class. Or even a Fram Racing filter ... those have a really thick can, and I think they are around 95-97% @ 20u.
The words Fram and racing made me LOL. It's hard to trust Fram because Fram is a swearword in my town. Also the Orange Can of Death expression comes to mind.

But I trust your judgement. So maybe it's time to let go of my mistrust of Fram.
 
The words Fram and racing made me LOL. It's hard to trust Fram because Fram is a swearword in my town. Also the Orange Can of Death expression comes to mind.

But I trust your judgement. So maybe it's time to let go of my mistrust of Fram.
Forget the name, look at the info and data, lol. You must have missed out on the OG Ultra being king here for many years, until First Brands bought Fram and started cutting corners. Some of that could have been pandemic driven, because Fram wasn't the only company cutting corners on their products after that event.
 
Forget the name, look at the info and data, lol. You must have missed out on the OG Ultra being king here for many years, until First Brands bought Fram and started cutting corners. Some of that could have been pandemic driven, because Fram wasn't the only company cutting corners on their products after that event.
I went several years without logging in at BITOG. So ya, I must have missed the OG Fram Ultra years.

I think many companies used the Pandemic as excuse to cut corners and raise prices. Many still are using the pandemic as an ongoing excuse. I mean that across a wide range of products and services.
 
Are those all UOA PCs off your vehicles?
No, they're all just PCs that have been posted on this site over the years.

I think looking at the >6u particle counts might be a better way to compare, as the higher efficiency filters will stand out better at that level.
The problem with comparing the 4u or 6u counts from older and newer tests is that it seems that Blackstone changed the way they estimate these counts. They were typically at least 6 ISO codes lower than the counts they tend to report today.

For instance, a typical PC for a Mobil 1 filter was 16/15/13 back in 2010. A more recent Mobil 1 PC test was 24/22/14. I think Blackstone used to use a standard curve for estimating the smaller particle sizes instead of measuring them, since the 6u counts were always 2-3 ISO codes higher than the 14u counts.

Even the 14u counts from older tests seem to be slightly lower than what's typical for newer tests, but it's hard to say whether this is due to a change in Blackstone's test procedures

The two Ultras from your table are included in my averages, but there are a lot of others that range from 24/21/15 to 24/23/16. For whatever reason, there does seem to be more variance in the counts for OG Fram Ultras than for other filters.
 
Baldwin's build quality appears to be top notch. Baldwin B35-S specs claims it filters 18 microns nominal. Wix 51036 claims it filters 21 microns nominal. What does that mean? Can we trust the manufacturers claimed specs to be truthful and accurate?
Baldwin gives specs for nominal efficiency (50%) and absolute efficiency (99%). The Baldwin filters that are 50% efficient at 18 microns are usually 99% at 40 micron,, which isn't very efficient.

I've seen one particle count posted for a Baldwin filter and it was ISO 16 at 14 micron, similar to the average Toyota filter. A K&N filter on the same engine was ISO 14.
 
The problem with comparing the 4u or 6u counts from older and newer tests is that it seems that Blackstone changed the way they estimate these counts. They were typically at least 6 ISO codes lower than the counts they tend to report today.

For instance, a typical PC for a Mobil 1 filter was 16/15/13 back in 2010. A more recent Mobil 1 PC test was 24/22/14. I think Blackstone used to use a standard curve for estimating the smaller particle sizes instead of measuring them, since the 6u counts were always 2-3 ISO codes higher than the 14u counts.

Even the 14u counts from older tests seem to be slightly lower than what's typical for newer tests, but it's hard to say whether this is due to a change in Blackstone's test procedures
Wonder if a call or email to Blackstone can shed any light on that. Could be the reason for such a mis-match over the years - or leaky leaf springs are showing the effect, lol. The UOAs I took my data from were all done around the same time frame, so comparing the filters I show to each other should be pretty good. The end result was of course that higher ISO rated filters resulted in better particle count data.
 
Wow, that's an amazingly crap result for a 'premium' filter.
It performed better than the Toyota filter which have been used on vehicles for 300k miles and more, and it doesn't leak past the bypass valve like many other "premium" filters.
 
It performed better than the Toyota filter which have been used on vehicles for 300k miles and more, and it doesn't leak past the bypass valve like many other "premium" filters.
Do you have a UOA particle count with a Toyota filter on the same engine with only the same 500 mile OCI?
 
It performed better than the Toyota filter which have been used on vehicles for 300k miles and more, and it doesn't leak past the bypass valve like many other "premium" filters.
I agree. I don't think the Boss is crap. I think it's actually pretty good, especially in regard to capacity, flow, reliable valves, and tough can. Similar can be said for Wix and Baldwin that I've been using for decades.

However, for less money than any of those, Purolator and Purolator One have better filtration efficiency, but less capacity and thinner cans.

I don't think Boss, Wix, Baldwin, or Toyota/Denso filters are crap, but they do have different functionalty goals/specs than what I'm looking for. I want more efficient filtration (like Purolator & Purolator One) while still having good valves, adequate flow, and a tough can like Purolator Boss, Wix, and Baldwin.

Unfortuneately, Purolator and Purolator One have thin cans, which makes me nervous for driving on gravel roads because flying gravel can hit an oil filter can (and potentially puncture it).
 
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It performed better than the Toyota filter which have been used on vehicles for 300k miles and more, and it doesn't leak past the bypass valve like many other "premium" filters.
You mean the filters that show vastly lower particle counts, despite the hypothesized leak potential?

The fact that the known-worst-filtering oil filter available for Toyotas performs about as well as a Boss, does not constitute a recommendation of the Boss as a 'premium' (aka expensive) filter, IMO.
 
I did a particle count test on a BOSS PBL14476 at the 500 mile mark. I never got around to doing it again because of costs. The ONE filter is known to filter down to 20 microns. I little better than the BOSS. I do find my results adequate enough to stay with the filter.

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I don’t know why they put number of particles as less than one. I guess some arithmetic cut them into pieces.
 
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