Reuse a used oil filter for high media efficiency?

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So most of us buy oil filters for their dirt holding capacity and their ability to trap contaminants in our oil on each pass. But is the best filter for our vehicle the one we just threw in the garbage can? Is that partially plugged used filter, efficiently filtering smaller and smaller particles with each OCI, the best choice?
 
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Severna Park, MD
It probably would be the best, up until it began to open the relief valve or whatever due to reduced flow. How would you know when that point it about to be reached?
 
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Without instrumentation (such as filter differential pressure correlated with oil flow rate) I will continue to change my oil filter even after our vehicles' powertrain warranties have expired. In industrial applications I'm used to filter replacement based on differential pressure but my industrial experience is primarily on systems using centrifugal pumps, not positive displacement pumps. Even then, I'd need some sort of rate-of-change alarm for example if a filter element is compromised (like a tear in the media) which causes the differential pressure to drop as well as pre-alarms, or I could well find a collapsed element (and even collapsed center tube) when I'd go to change the filter. Which then raises the question of purging the instrument taps with a clean fluid so those don't plug, etc. I just don't see a favorable cost to benefit ratio for this application personally.
 
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Only way to know would be to have a delta-p sensor across the oil filter. I can maybe see auto makers using a delta-p sensor on future autos. It would be one way to cut down on wasting resources by not changing the oil filter until it's time. It would also let you know to change it due to plugging up early if that was the case, thereby preventing the filter from going into bypass more than it should.
 
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Central Florida
I have a Mobil 1 oil filter on my dad's Honda for the past 3 years. He only drives 2500 miles per year, if the engine is clean (no sludge) with very low miles.... I feel changing the oil filter would be a waste of good money. No way this oil filter would get 'clogged' at the 4 year / 10,000 mile interval. I just do yearly drain / refills.
 
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Most mid-range and high-end oil filters have dirt holding capacity of about 10 grams or more. In a non-sludge engine it is not possible to have more than 10 grams of contaminate particles in less than 20k miles. I changed oil + filter in my 15 years old E430 few months ago, the cartridge oil filter after 22-23k miles (I reused once) didn't have any visible debris on any pleat, and the media didn't have any sign that it is about to exploded. From what I saw on that filter it looked like it can be used for another OCI of 10-13k miles.
 

CT8

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Originally Posted By: HTSS_TR
Most mid-range and high-end oil filters have dirt holding capacity of about 10 grams or more. In a non-sludge engine it is not possible to have more than 10 grams of contaminate particles in less than 20k miles. I changed oil + filter in my 15 years old E430 few months ago, the cartridge oil filter after 22-23k miles (I reused once) didn't have any visible debris on any pleat, and the media didn't have any sign that it is about to exploded. From what I saw on that filter it looked like it can be used for another OCI of 10-13k miles.
Depends upon the quality [dirt] of the air intake.
 
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Take the filter's temp with an IR gun when the engine is completely warmed up. When the temp reads lower than the initial reading on a new filter after the vehicle is completely warmed up, change it. Next time change it a bit sooner. If the filter is at it's operating temperature it's working. You'll need the IR gun because the temperature drop will start at about 10F below the reference reading at the surface of the oil filter can and can be as high as 50F. In a worst case scenario the oil filter can might be cool to the touch. Use a reference reading like the same spot on the bottom of the oil pan to confirm normal operating temp. You must perform this drill just after the engine hits normal operating temp because heat soak will tend to hide or minimize the shift in the filter temperature if you wait too long. The run time for a filter change should be the amount of fuel used because that's a better indicator of the amount of oil filtered then odometer readings or hours of operation. For a daily driver you can then figure back to the mileage needed to keep your maintenance simple. No one will go to the extra effort to track fuel used in day to day operation. Cut back the next change to 80% of this reading. This method is used to help setup and confirm maintenance schedules for emergency generators that must be as lite as possible, run at very precise speeds and are air lifted and often installed in places that are not easy to service but must be very reliable, gen-sets that may be left in place for long periods of time in the worst climate possible. Lab tests are fine but hands on testing is needed to certify these systems before they are accepted for deployment. This round-about oil filter test has been backed up by lab analysis and every new design is subjected to this procedure. Evidently it's more repeatable and accurate as far as filter function and capacity than using oil pressure delta readings which would have been a lot easier. Pressure delta readings are used for the air filtration system and crankcase ventilation systems. If you've never done this kind of work it's your turn to take a shot at it. As a side note, some of the gen-sets use a synthetic oil that would be classified as a 0w-5 in automotive terms.
 
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Good question. I like the idea, but knowing exaclty when the filter is completly in bypass 100% (and needs replaced) would be pretty difficult. I'm still convinced effenciency isn't everything though. Toyota OEM filters being my prime example.
 
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Texas
OneEyeJack: Since the oil flows along the inside skin of a dome-end bypass oil filter WHETHER OR NOT the filter is bypassing, how is temperature of the filter shell going to tell you ANYTHING about the status of the filter? And even on a base-end bypass filter, a fair amount of oil will still be going thru a partially-clogged media even if its clogged enough to open the bypass valve as well.
 
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S California
Originally Posted By: 440Magnum
OneEyeJack: Since the oil flows along the inside skin of a dome-end bypass oil filter WHETHER OR NOT the filter is bypassing, how is temperature of the filter shell going to tell you ANYTHING about the status of the filter? And even on a base-end bypass filter, a fair amount of oil will still be going thru a partially-clogged media even if its clogged enough to open the bypass valve as well.
This test system works fine, every time. It's very repeatable. In the case of units in Russia they simplify the test by using the hand touch method. If they can fell that it's cooler they end the test. We sold a bunch of units to Russia in 2003.
 

SilverC6

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Consistent with this logic, wouldn't the best new filter be the one with a relatively small amount of high efficiency filter media? For example, wouldn't a FRAM Extra Guard be a better choice than a FRAM Ultra since the Ultra will take much longer to plug and offer this higher efficiency filtration?
 
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Originally Posted By: SilverC6
Consistent with this logic, wouldn't the best new filter be the one with a relatively small amount of high efficiency filter media? For example, wouldn't a FRAM Extra Guard be a better choice than a FRAM Ultra since the Ultra will take much longer to plug and offer this higher efficiency filtration?
The Ultra is high efficiency when it's not plugged. I don't think the ISO 4548 test ranks the filter's efficiency based on when the filter is plugged up close to bypassing. I don't think a full synthetic media (depth filtering) "plugs up" like non-synthetic media (surface filtering) does.
 
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Depth filtration is indeed different than surface filtration. Media for depth filtration is designed to capture particulates in the media rather than building a surface layer of filter cake. The Fram Ultra and Pennzoil Platinum HE filters advertise density depth filtration using 2 layers of synthetic media. This allows for an outer coarser layer and inner finer layer of filtration. It's easy to see why Fram went to all synthetic media in the Ultra, as the Xtended Guard with the outer layer of cellulose media was designed for surface filtration, so not the best design for utilization of 2 layers of media.
 
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WI
Originally Posted By: Motorking
Only true with air filters, not with oil filters.
Please explain how big dirt plugs big holes in filter media only applies to air filters.
 
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The Old North State
IMO, two different subjects are being addressed at this point. First, there is little debate that an oil filter becomes more efficient with use. The particles caught in the media with use increase efficiency. That of course is up to the maximum holding capacity of the filter/filter media, beyond which increased filter bypass becomes an issue/factor. The second, which appears to be the question being asked here, is the filter currently in use the best filter choice? As long as the filter used won't exceed it's holding capacity over the second oci, as far as efficiency goes, it could very well be. And in moderately clean and well maintained engine, it's even very likely. I'd say it's especially true when one is talking about rock catcher oil filters such as the Toyota Denso and Honda A02 oem filters that start in the 50-60%@20um range. That said, when it comes to oil filters starting in the middle to upper 90%@20um range, imo there's little significant gain efficiency that points to using them twice as the main reason to do so. But if one is also considering ROI in addition to efficiency of the latter, then that would increase the logic of using the filter more than oci. Again, as long as not exceeding the filter's rated holding capacity. My .02
 
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