Toyota oil filter light leak

Just curious if this oil filter leak or seep is significant or it's like many other things in a car which are not "perfect".

For example we discuss and/or analyze engine oil to death ... And the quality of the oil (i.e. approvals, etc.) being up or down some doesn't seem to impact much in general if you follow manufacturer recommended oil/OCIs. Basically it falls under overanalyzing category which I am guilty of as well but also aware of it. :ROFLMAO:

So this oil filter issue (assuming that is valid) fall under that category and/or maybe manufacturers (in this case Toyota) are well aware it but it's not significant or a don't care!
I agree. The high efficiency vs OEM efficiency debate is legit. But paying a premium for a high efficiency filter thats defective and affecting its efficiency is another debate. Better off just running a $6 OEM filter.
 
So does this oil filter issue (assuming that is valid) fall under that category and/or maybe manufacturers (in this case Toyota) are well aware it but it's not significant or a don't care!
I highly doubt they purposely design oil filters to have a built-in constant internal leak of dirty oil past the media. One of the top design requirements for an oil filter should be "design it for no internal leakage".

The other part of the equation is manufacturing. If they can't manufacture a product to the engineering design and specs, then that's a failure too. That's basically the issue with the ruffled up leaf springs causing a leak gap between the leaf spring and end cap. These ruffled leaf springs haven't been around forever, and they use to be made flat and smooth in the past. It's sloppy manufacturing going on.
 
What about the voids in filter media. Like some filters from Japan, the holes are extreme.
A bypass valve could be made with a taper where it fits in an end cap that has a almost matching taper. Those areas shouldn’t end up ruffled in manufacturing. It would seal under spring pressure something like a compression fitting but not that tight. Very simple, wouldn't cost more to make.
 
You mean a leaf spring? ... which isn't really the bypass valve.

I'm pretty much going with filters these days with a coil spring instead of a leaf spring, and also no louvers. Better design aspects overall.
 
A tapered cork is a very old idea. They use a cork to do the bubble point probably.
WCW has a new video on a Honda Japan filter, interesting. Seems to have caught a lot of debris in the can over 6k, but the media is porous.
When Honda went to Fram for filters, they specified their own media design, less efficient. They could have used the efficient EG media instead. Remains mystery.
 
It still caught a lot of debris because the size of that debris is huge, even compared to the big holes in the media. The stuff you can't really see is what got through at some level due to the efficiency of the media.
 
It still caught a lot of debris because the size of that debris is huge, even compared to the big holes in the media. The stuff you can't really see is what got through at some level due to the efficiency of the media.
The media pic show small debris right next to a hole much larger. I know your ideas on efficiency but was wondering about why major engine makers specify oil filters with lower efficiency numbers when theycan specify higher. Subaru, Honda, Toyota, Ford maybe.
 
The media pic show small debris right next to a hole much larger. I know your ideas on efficiency but was wondering about why major engine makers specify oil filters with lower efficiency numbers when theycan specify higher. Subaru, Honda, Toyota, Ford maybe.
Sure, even with some "big holes" in the media, it's still going to catch some smaller stuff. Just look at a filter's efficiency vs particle size graph like seen in Ascent's ISO 4548-12 testing. Even a filter that's 50% @ 20u will catch some particles less than 20u, but not nearly as many as a filter that's 99% @ 20u. Ford Motorcraft/OEM filters are more efficiency that the Asian OEM filters ... they meet USCAR-36 which specifies an efficiency much higher than 50% @ 20u.
 
I heard it's because they prefer flow over filtration

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When testing a spin-on filter, e.g. Amsoil EA15K13, based on ISO 4548-12, are the tests based on oil flowing in and out of the filter as if mounted on an engine?

I ask because the Amsoil website seems to reference the efficiency to the media with footnotes to ISO 4548-12. A new filter box also references the advanced media filtration. So is it the media's filtering or actual testing of a complete assembly meeting the ISO standard?

Also, their current Product Data Bulletin shows the construction having "Louvered Center Tube (Inside)", but the filter I cut open the other day no longer uses this construction method. WCW's test of this same filter last year has the metal, louvered center. Thank you.

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^^^ Yes, if an oil filter it tested per ISO 4548-12 it has to be the whole filter assembly, just like if it was mounted on an engine. This thread really gets into the whole ISO 4548-12 testing method.


The Royal Purple tested is essentially the same guts as the Amsoil. Graph from post 368 in that thread.

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^^^ Yes, if an oil filter it tested per ISO 4548-12 it has to be the whole filter assembly, just like if it was mounted on an engine. This thread really gets into the whole ISO 4548-12 testing method.
I started reading through the 29 pages of data, but after about 45 minutes, realized I didn't comprehend enough of what I'd read to be able to answer such a simple question. I appreciate your making it simple for me.

What would you do knowing something you bought is no longer built in the manner shown in the current product data bulletin? One of the ruffle examples in other threads is from the EA15K13 I recently removed from the Pilot. I have two remaining new filters, which I no longer plan on using. I can request a refund from Amsoil, but it's only about $25.

I'm also thinking of shipping one to a forum member who is highly regarded and considered one of the most knowledgeable when it comes to filters. I'd like them to do an analysis since they have the experience to do it correctly.
 
I started reading through the 29 pages of data, but after about 45 minutes, realized I didn't comprehend enough of what I'd read to be able to answer such a simple question. I appreciate your making it simple for me.

What would you do knowing something you bought is no longer built in the manner shown in the current product data bulletin? One of the ruffle examples in other threads is from the EA15K13 I recently removed from the Pilot. I have two remaining new filters, which I no longer plan on using. I can request a refund from Amsoil, but it's only about $25.

I'm also thinking of shipping one to a forum member who is highly regarded and considered one of the most knowledgeable when it comes to filters. I'd like them to do an analysis since they have the experience to do it correctly.
If the leaf spring was stamped flat and smooth like it should be, then it would most likely hold the 99% @ 20u ISO 4548-12 efficiency claim - like the RP did in Ascent's testing. A filter that tests at 99% @ 20u could only leak internally 1% or less to make that level of efficiency. If it leaked 5% from a perfect 100% efficiency then the efficiency would drop to 95%. A 10% leak would drop it down to 90%, etc.

Filters with leaf springs have been stamped well for a long time until recently. The people that manufacture them need to be asked why they can't seem to do it very well now. It can't be that difficult.
 
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If the leaf spring was stamped flat and smooth like it should be, then it would most likely hold the 99% @ 20u ISO 4548-12 efficiency claim - like the RP did in Ascent's testing
But RP is a clone of Fram Endurance isn’t it? Are you then assuming the RP tested in both Ascent and its ISO had no ruffles or leaks?? In the top pic there doesn’t “appear” to be ruffles…. But if you zoom on the bottom pic, there still appears to be slits below the leaf springs on both filters in some spots.

Endurance vs RP
👇👇

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