Source of the below is post 183 here:
http://forums.nasioc.com/forums/showthread.php?t=1623020&page=8
It kind of sounds like PR blather some management person gave a customer rep to send out in response to an inquiry. It doesn't sound very engineering specific; mainly generalities.
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presumably from an "insider".
"Per your request, I have same[?] information which differentiates the new Subaru/Honeywell Oil Filter (made in Canada) p/n: 15208AA12A from various aftermarket competitors:
1) The new Oil Filter (made in Canada) p/n: 15208AA12A is the OEM line installed filter for all 2.5L and 2.5L turbo engines built at Subaru Indiana Automotive. In order to pass Subaru's rigorous test requirements, the new filter's filtration performance and test specifications were designed so that they far exceeded any aftermarket "one-size-fits-all" filter.
2) The filter's pleated media has variable density paper. The variable density improves the filter's ability to trap contaminants. The variable density paper is more expensive than common aftermarket filter paper.
3) The filter's Relief Valve feature allows oil to flow to the engine even if the filter is clogged. The value's torque setting was tuned by Subaru and Honeywell specifically for Subaru engines.
4) The filter's Anti-Drainback Valve is made of silicone. The silicone material is used for optimum performance and sealing to prevent oil from draining out of filter when engine is shut off. In general, aftermarket filters use lesser materials.
5) The filter's external gasket is a molded P-Ring seal design. The P-Ring design provides superior sealing for solid contact between the filter and engine. Many aftermarket filters use a common lathe cut(non-molded/less expensive) gasket for sealing.
I hope this abbreviated explanation clearly shows that the new Subaru Oil Filter is far superior in overall design and materials to lesser aftermarket products."
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