Most 2003 Ford-F350 Super Duty trucks did not come equipped with a cabin filter. The cabin filter was an optional feature installed by using Ford kit number F65Z-18D477AA. If this kit was installed on the F-350, it has a cabin air filter. The easiest way to tell if you have a cabin air filter is by locating it. If your F-350 has a cabin air filter, you'll need to replace it every 15,000 miles to keep your air conditioning performing well and your interior air fresh.
Turn your ignition off and remove the key. Access the passenger-side floorboard by entering the F-350 through the passenger side door.
Look closely underneath the glove box. There is a black plastic cover mounted on the rear. Remove the five Phillips-head screws from the cover. Pull the cover down to remove it.
Inspect the area behind the cover. If the F-350 has a cabin air filter, you'll see a rectangular filter-access door with tabs on the end. Squeeze these tabs to remove the cover. The cabin air filter is behind it.
