We run a heavy-duty Ford L8000 truck that has a Ford 7.8L diesel engine in it. It is used in very harsh operating environment that sees a lot of loose debris through the air that get picked up by the air filter. We put a wire mesh screen over the filter intake to prevent some of the larger pieces from plugging the filter. The mesh will often get covered to the point where the engine doesn't perform as it should so we open the hood and wipe the mesh off and it' good to go again. Now I took the filter out ( a Fleetguard AF886 ) for inspection and noticed there was a spot, right where the intake is on the filter housing, where the pleats were darkened and torn. Needless to say, I replaced the filter but was wondering what might have caused this. Could the high restriction of the wire mesh covered with debris cause the filter to tear in on itself?