Originally Posted By: HM12460
A little off topic here, but didn't the old VW bug's have a cleanable/re-usable screen used for oil filtration?
In function, it's not a filter. It's an inspection device. You can tell the general condition of the engine by the type and quantity of [censored] caught in the screen, be it bits of carbon, aluminum or copper, sludge, etc.
One of the reasons ultra-purists and old-timers object to a spin-on filter mod is because the filter, well, filters out so much that nothing gets caught in the screen, so you can't rely on inspecting it to tell you what's up with the engine.