This will be my last post in reference to the topic. When a cotton filter is used, the oil retains the debris while still allowing a very high flow. When a paper filter is used the debris just hangs out on the outside of the paper and blocks the pores. If someone can't properly oil their filters then chances are they need not even pop the hood. There is a filter cleaning spray and the bottle of oil. Just soak the filter in the cleaner, wash it off and apply the oil to the OUTSIDE of the filter. So if nobody can figure that out, we have a major problem. To attempt to claim that an oiled filter doesn't perform well when dirty is just plain laughable. No filter, no matter the material, is going to perform as well dirty as it is clean! Who is to know when they are dirty??????? The same people who know when a paper filter is dirty!
This is from Ford's site.
•Oil-treated filters have at least twice the capacity of non-oil-treated filters
•Available filters are primarily oiled
Since GM doesn't sell much for air filters(only one is an oiled cotton piece) of course you won't find them. I ask you and anyone else who really cares, when is the last time you heard of a catastrophic failure due to an upgraded air filter? Again, this is turning into a rediculous argument so this will be the last time I post here. Just understand that because you don't want to spend the extra money on a filter doesn't mean you should start shouting about something you don't have much experience with. I've been running oiled filters for the last 200k miles on my 94 Sierra. Let me rephrase that. I have ran a single oiled cotton filter on my 94 for the last 200k. Since these filters are designed to be cleaned and re-installed there is no need to ever buy another. It isn't a debate as to which allows more air flow, we all know that oiled filters, by a long shot, are better breathing units. The only thing you are going by is that someone told you they allowed debris to enter your engine. That is false. There are far more pieces of debris entering the engine from the fuel system than any air filter would allow. All kinds of grit, dirt and rust particles are pushed through every time you start the engine. I'll gladly take my much better breathing oiled filter, and the improved power to go with it, over a less expensive paper filter. And I think that if you asked around, anyone who has ever had one will have nothing bad to say about them other than they open the intake up and cause more in cab noise. I've ran many, many trails and mud holes in my off road vehicles, all of which had oiled filters on them, and never had a failure. And that is with mud, water and dust literally caking them. This is a good thing for people to hear, they get both sides of the story. If I get a chance I'll toss the stock air cleaner assembly back on and get a dyno run, then the oiled filter and do the same. Last time I dynoed the truck it was right at 190hp to the wheels.