Originally Posted by StevieC
CR94,
1) When does a pleat ever tear free unless it's a Purolator?...
2) I don't worry about that, I think quality filter manufacturers over build the filters flow to protect them from engine damage claims. ...
3)Huh? End-caps would be better in this regard because the media isn't loose against the housing/cap ...
4)If there is an o-ring like the filter above that has end-caps I don't see how that would be an issue. ...
1) The only filter I ever opened that had torn media was not a Purolator. Other brands turn up with tears occasionally in this site.
2) Shrinking the media area never helps, especially with tiny filters. Endcapless allows deeper pleats.
3) There's a reason why oil filters have center tubes. Endcapless allows the inner pleats to be fully supported by the center tube of the housing. Cartridge filters with end caps have a radial gap between the pleats and the center tube, much larger on some than others.
4)That one is harder to explain without pictures. Some cartridges, including those for certain 1.8-liter Toyotas (Corolla, Prius, Matrix ... ), do not use o-rings at either end. The rigid end caps have to seal against rigid metal ends of the housing and cap, so the end of the filter must be accurately parallel to the end of the housing. The filter will sit cocked slightly and leak around the end if its centerline isn't perfectly perpendicular to the end caps and it's too rigid to conform. I have an unused cartridge with exactly that defect.