Helping JimT out with an inframe ...

[JimT]

I've never had the level sit this low before. It's like there's a very small amount of air finding it's way into the system somewhere. If I fill the Davco up with fuel it takes 1-2 full days of driving for the level to drop down below the clear housing. This only started happening recently so there's obviously something that's changed. When I looked at it last night the fuel level was actually just below the metal bottom of the filter itself, barely above the level where the fuel lines connect.

Sitting here thinking about it, I remember when I changed the Davco unit on Tuesday that of the 2 fuel lines, the one going to the primary filter had some residual fuel in it, but the one coming from the tank didn't. Just another reason to inspect the supply lines and the tank vents. Could be a small pinhole or crack forming in one of the lines letting some air in, or plugged up vents causing a restriction (and still sucking in air from some tiny crack).

One final thing, not sure if it's related, but I noticed yesterday that the fuel level sending unit seems to be going bad as the fuel gauge started bouncing around randomly. Maybe it's time to just replace the sending unit, vents and all the tank fuel supply lines.