Need Help, Fuel draining back

[amermextrucker]

last 2 oil changes on my truck Davco 382 has no fuel in it. 1st fuel filter went 20k miles and no visible fuel . On this recent service im at 1500 miles and no visible fuel yet. In the past fuel starts building after 3-4 k miles after service. Im keeping an eye on it. I watched video rawze posted on how to change. Truck fires right up , but i do notice a tad bit less power , maybe its my mind messing with me.

Im going to go to 5k miles and change filter out. If this continues ( no fuel in filter ) what should i be looking for ? my concern is filter is not doing its job and might damage something ? thoughts ? TIA.