I have a theory why so many Purolator filters are tearing: The bypass valve has a very small spring which does not allow it to open up very far during cold starts. This cold winter we just had meant that almost all oil was flowing through the bypass valve at startup. If all the oil can't get through that small opening, then it's going to tear the media. Here's my rationale: I cut open the PureOne filter on my wife's car last weekend (no filter tears) and tried to open up the bypass valve. It barely opened, no matter how hard I pressed it. Compared to other bypass valves I have seen on other filters, the PureOne valve has a very short range to open. This can be explained by the shape of the bypass valve spring: (photo borrowed from 2010_FX4) Unlike a coil spring used on some other filters or a large flat spring on others, this has a tiny spiral-shaped spring. Sure, it will open up at the right pressure, but its range of motion is quite small due to the size of the spring. Here is a photo from ten years ago on a failed SuperTech ST3614 filter I had with the old clicker-type bypass valve: Look similar? (I know, bad picture) I had two of these SuperTech filters that failed back-to-back. A few months later, Champ Labs discontinued making those filters with the clicker-type bypass valves. I never could figure out how they could possibly open up. I guess Champ Labs eventually came to the same conclusion. If my hunch is correct, we will likely see less failures in the future because the Polar Vortex is behind us. But some people like revving their engines when they start their cars, so we may still see more failures until Purolator changes this design.