Hello everyone, I'm coming on here hoping to find answers. I have a 1998 GMC Jimmy ,and over the past week i have noticed a small fuel leak. The weather here in PA has prevent us from really investigating it as we don't have a garage (taking it to a shop is out of the question financially). I was in a bad habit of topping it off ,but i never had leak before until last week. I didn't smell ,or see anything upon fill up it wasn't until i parked it that i noticed anything. I was in a parking garage ,and noticed a fuel smell. I looked underneath ,and could see one part of the frame was dripping wet. Once i touched it ,and smelled my hand i smelled fuel. I kept on an eye on my fuel gauge over the course of the night ,and over the course of 12 hours i lost less than an 8th of a tank. Once the tank seemed to get below 3/4 or so the leaks stopped. I checked it the entire week at every place i went ,and the spot i seen the leak was bone dry the only wetness was from the snow ,and water on the road. Tonight i needed fuel so i refilled the tank from 1/4 to full. I watched underneath while it filled ,and there was no leaks. i brought it home ,and went out to get groceries out of the truck an hour or so later. I looked underneath ,and once again it was exactly how it was last week. I checked my gauge ,and it's reading full. I'm not having any issues starting the truck ,and i don't seem to have any power problems ,or anything. The leak appears along the frame about a foot away from the rear driver side tire. Anyone have any idea what is causing this leak. My dad ,and i are thinking it's the return line as it only happens when the truck is shut down ,and sitting after running.