The 2005 F150s had several gear options from the factory. Your best bet would be to check your F150's door sticker and look up your axle code. Wheels alone really won't effect much in regards to gearing and final drive ratio. Your tires are what effect RPM and powerband, and your choice of gearing is really going to depend on what diameter tire you're going to run, what kind of acceleration and performance you're looking for, and how much of fuel economy hit you're willing to take. Your best bet would be to call us directly at 623-434-5277 so we can get more specific about what you're going for.