Originally Posted By: bbhero
You don't think that the filter doesn't absorb anything?? It does. Good bad or indifferent it does. Period end of story. It does hold the oil too. Which is a very fair point. But to say that it doesn't add or absorb oil over its life is not accurate. weigh a filter before and after you pull it off..... Tell me there is no difference. Try it. Report back your findings.
That's not what I said, and it's not what you said either. The issue here is "absorb".. and "absorb oil over its life"
I pre-fill my filters whenever possible during an oil change, so I'm 100% aware that filters hold oil. I do not need to 'try it and report my findings.'
I would never say a filter "absorbs" oil. That would imply that the oil slowly soaks into the filter over a period of time, which is ludicrous. I am aware that a filter has a holding capacity, and I'm sure that nobody here would disagree that the filter DOES end up increasing the overall 'sump capacity' of an engine by whatever volume it is capable of holding, but your initial statement didn't speak to this.
The wording "absorbs oil" implies that after you've initially filled the engine/sump with oil, and at some point down the road, the filter will have absorbed an ADDITIONAL quantity, over and above the initial fill, and will continue to require multiple top-offs due to it's consumption of oil as a result of absorption. This just simply can't happen.
Using my Fusion's engine as an example.. The engine's sump is roughly 5 quarts. The filter I use (usually an Fl400s or equivalent) holds approximately .4 quarts.. this means that if I add 5.4 quarts to my engine during an oil change, run it, and then check after it's cooled back off, it SHOULD be right at the full mark. 3000 miles later, if the engine has not burned or leaked oil, it should be at, or very close to, the full mark. It should NOT be low, and should NOT require adding any additional oil. Why? The filter has not "absorbed" any oil.. Whatever soaked into the filter media during the initial fill/run, has completely saturated the media and will not absorb further.
In the OP's post, he stated he had to add additional oil down the road, long after the initial fill, and long after the rather short period that would have been required for the oil to saturate the filter media. Your statement implies that the filter will be continuing to absorb oil into the media (or, I hope you weren't implying that it would absorb into the filter casing) for thousands of miles down the road.