Where is the cabin air filter on a 2006 ford f250 5.4L engine?

The cabin air filter on a 2006 Ford F-250 with a 5.4L engine is located behind the glove box. You'll need to remove or at least significantly lower the glove box to access it. There are usually screws or clips holding the glove box in place. Consult your owner's manual for precise instructions and diagrams as the access method can vary slightly.