No driving lights

I have a 2005 F350 dually. It is a crew cab with a flat bed and I just replaced a fuse that looked fine (#20 fuse) and got my reverse lights back. I have no driving lights? I have turn signals and brake lights and now reverse lights. The flashers work too. Would like some help diagnosing this. Is there a fuse I'm missing? Is it under the dash or is it under the hood? Could it be a ground? The lights all used to work weeks ago. Going over a railroad track may have loosened something? Thanks for any help or knowledge you can bestow.