Relevance of changing the oil filter every OCI

It's a personal thing. To me using the same oil filter after an oil change, is like taking a shower, and putting the same underwear back on.
:)
standard filters will pass small debris. those also do some harm. only way to remove them is to replace oil.
more like showering and swapping underwear several times a day
 
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I agree. Plenty of engines out there with very high mileage, that have only seen $3 orange Fram filters.
Marketing works. Just like so many people expect to see a properly maintained engine to be full of sludge if "conventional" oil is used.
 
Not a big deal, there's only about 4% difference in efficiency. Not enough to spend 2x for the extra efficiency.
Depends on what filters you're comparing. There are some pretty expensive filters that are not very efficient (like 50% @ 20-25u or 99% @ 35-40u). You don't always get higher efficiency based on the cost of the filter.

And also looking at how the efficiency drops off below 20u should be compared. That data is hard to obtain. Every wear study says it's the particles below 20u that cause the most wear. That's why for longer OCIs a higher efficiency filter helps (a bypass filtering is a step further), or do shorter OCIs to get the debris that is not filterable out of the sump.

If all these oil filters were basically the same price, which one from a filtering standpoint would you want?

 
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If a standard paper element oil filter lasts 20,000 mi or 24 months (manufacturers recommended service interval) I wonder how long an Ultra should last?
 
Just did an oil change and i still wanted to open the filter housing to take a look and sure enough, it was still perfect.
 
I was cool by changing my oil filter on my 1969 Lemans EVERY oil change when the manual said only every other.

Round and round she goes, and where she stops? She simply doesn't. Wide lapels, tie-die and paisley came and go.....
 
I was cool by changing my oil filter on my 1969 Lemans EVERY oil change when the manual said only every other.

Round and round she goes, and where she stops? She simply doesn't. Wide lapels, tie-die and paisley came and go.....

My much more recent Honda manual still says every other.
 
Some people use their filters for 2 OCI's, or more. Others like myself feel if the oil is being changed why leave up to a half a quart or more of dirty oil behind? Do what you feel is best. Topics like this can get heated real fast.........
Do filters on most passenger cars really hold that much oil? I would think maybe 1/2 quart at most.
 
Do filters on most passenger cars really hold that much oil? I would think maybe 1/2 quart at most.
Maybe one of the largest passenger car filters, like a Purolator 30001 would hold about 1/2 quart. Most avgerage/medium sized filters hold about 8 oz. When an oil filter is removed, there is also oil in the main gallery that also leaks out the filter mount.
 
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Maybe one of the largest passenger car filters, like a Purolator 30001 would hold about 1/2 quart. Most avgerage/medium sized filters hold about 8 oz. When an oil filter is removed, there is also oil in the main gallery that also leaks out the filter mount.
I use the XG8A, the cousin of the PH8A both IIRC cross reference to the 30001. I've used that filter since the 1970's when I started driving, and still do today. So I base my comments on the filter I've used the most in my life. When you factor in the oil that drains out the filter mount it's easily a half quart or a little more. I don't want that dirty oil left behind.
 
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