I finally decided to change the air filter on my '05 Ford Freestyle. This is a Motorcraft filter. I installed this filter at 88K miles. I opened the air box up @ 92K and installed a restriction gauge--but didn't change the filter. I did actually visually inspect the filter one a year, but without removing it or opening the air box. I have to lift the air box out of the way to access the transmission dipstick, so I can look inside and inspect the filter without actually opening the box. The business end: [img:left][/img] Pleats opened up: [img:left][/img] Top side: [img:left][/img] The filter is 3.5 years old. I was going to go 4 years or until the restriction gauge told me to change it; however, since I had to open the box up once--and since I never went this long on a filter before--I was a bit concerned about the gasket material. I should mention that the filter gauge didn't move at all. The restriction was never more that 2kPa. I tested the filter minder when changing the filter and it works fine. My general thoughts: -the gasket was fine, still pliable and no cranks. -visually, it looked terrible on the underside--like it would be "choking the engine" -I didn't need to change it. But, since I already opened the air box, I did. I probably won't open the box for another 5 years. Given my climate/conditions, I probably don't need a restriction gauge. Time/gasket life will be the determining factor, not dirt. I plan on going 5 years on the next one, or if the filter gauge hits 4 kPa (which I seriously doubt will happen in 5 years). YMMV and all that. It's just not very dusty here, and the climate isn't harsh on gaskets. Flame away!