Yes if they print it on every box as 20 microns it is false advertising.
Purolator Boss PBL24651 6,075miles C&P
- Thread starter BrendanC
- Start date
BrendanC
$100 site donor 2024
they do state in fine print that it’s referencing the PBL30001 but even it doesn’t meet the 20um rating.
And there's a guy in another forum, that runs those boss filters, and he's gotten well over 300,000 miles, they must be doing something right.. I have personally never used one. I have used a Pure one.
Yep, that's false advertising for sure. Purolator's website says 99% at 25 microns (not 20) for the PBL30001, but still not even close to >46 microns. M+H needs to clean up their website. Surprised that other filter maker's legal departments haven't sent a false advertising notice to them.
Engines with more wear can still run pretty well, but their mechanical health may not be as good (ie, less compression, more oil consumption, etc) compared to it having less wear over time.
Just making it to 300,000 is only half the story.
The BOSS is one of the least restrictive filters out there. I wouldn't say they're built like a tank though. The cans are pretty thin.
BrendanC
$100 site donor 2024
High flow and particularly thick cans being two relatively unimportant attributes for a passenger car oil filter.
A few PSI less of dP doesn't matter 99.99% of the time, and only would matter if the PD oil pump ever hit pressure relief. It's way less than 1 PSI difference under normal driving conditions compared to others tested by Ascent. The Ultra, Boss and Wix XP were essentially the same, within 1 PSI of dP even at insanely high flow rates (50 L/min = 13.2 GPM) with hot oil.
Would you all like to see ISO 4548-12 Oil Filter Lab Testing Comparison, Efficiency & Capacity, Pressure vs Flow, Bubble Point, and Burst?
You switched your temps here, but yes exactly. It's easier to heat a fluid up then to cool it down to reach a target viscosity. I also don't like to get fluids to hot. Around 40C is where I don't like to go beyond if I can help it. Nice graphs and homework on this equivalency!
bobistheoilguy.com
It helps with the prevention of filter bypassing, and reduces load on the oil pump. Both of these things are prioritized on race engines. Sometimes race engines even have no oil filter bypass at all, in order to limit damage when the engines fail.
Also, the oil pumps on some engines are in pressure relief at high rpm even when the oil is warm. For these engines, less restriction results in more flow and higher oil pressure at the bearings.
Even on a stock street car, there are filters that are twice as restrictive as the BOSS and they'll hit bypass pressure even in some of the intended applications.
wemay
Site Donor 2023
Great looking filter. Thanks for the C&P
I completely agree with you, I know he get oil analysis done about every other oil change..
What the oil filter bypass valve is set to is part of the design equation. The bypass valve setting (if done correctly for worst case senario) should take into account the flow vs dP curve of the filter, and not allow any filter bypassing with hot oil, even at high RPM.
Do a hydraulic HP to mechanical HP calculation, and you'll see the difference in pump load is basically nothing (like less than 0.1 HP at high RPM) when the dP difference across the filter is only a few PSI. At normal cruisng around RPM, it wouid be so near zero that any difference could never be detected.
Any race engine that uses an oiling system with the filter bypass valve gone or disabled (like the GM "hot rod" guys use to do by blocking the block filter bypass) better be using a pretty low dP vs flow filter, or make sure the oil is fully warm before going nuts on RPM. Some of those guys imploded the oil filter because it couldn't bypass, and that in turn could possibly send debris into the engine ... it can be a risky mod.
Only those with insanely high output oil pumps, like those over-designed Subaru oiling systems. lol. I still don't really believe they flow that much oil in real life use, but that's another subject matter. If they did flow that much at high RPM, the sump would literally suck dry and the pump would suck air and starve the engine of oil flow.
You're probably again talking about the crazy oil pumped Subarus. Even my Z06 oil pump only flowed around 7 GPM at redline, and no oil filter used on that engine would get close to bypass, or make the pump hit pressure relief when the oil was at 200+ F.
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They are an extended mileage filter. The racing segment has no need for extended mileage filters. I've watched some YT videos & these Boss's catch a lot of debris.
Extended OCI mileage rated filters (which will have a higher holding capacity) should be more efficient, not less efficient. As has been mentioned in many threads, the longer the OCI the better the oil filter efficiency should be in order to keep the sump cleaner over the longer OCI.
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I would use that filter for twice the interval. Waste of time and money. IMO.
BrendanC
$100 site donor 2024
that is you, not me. this is from our fleet that shortly will be transitioning to HPL and running fram endurance filters to 12k.
Great outcome on the filter and your oil looks great too!
