Main filter with about 30-34k on the clock.
Changed it simply because I was tracking down a fuel system restriction...still looking for it...think it is the device that limits air to/fro the fuel tank vent
This filter has had WVO, biodiesel, and regular petroleum diesel ran through it...
...the goo looking stuff is the glue they use inside the filter.
BTW Yes I do have the right socket (shallow and such) and whatnot to properly remove the tank strainer