Interesting. A paper filter was already installed on this vehicle when it came to me. I wasn't even aware that the original filter was of the oil impregnated steel mesh variety.
Only after I stocked in a supply of paper filters did I become aware that a reproduction of the wire mesh filter is available.
However, I keep the paper element clean and blow it out with compressed air regularly so it hasn't become so restricted as to alter the RPM when installed.
I've tested this with an RPM gauge and I can remove the air filter and put it back on with no change in rpm.
When the truck first came to me, however the paper element in place was so filthy that the engine would barely run.
