Seen them glass filters,Alway's an air pocket in em" Is the truck stalling or dying?If not it's not a problem.Seen a few that never kept it full but it get's enough fuel anyway.There isn't much pressure there.Look at some lawnmowers with them plastic see through filters,they look empty for the most part but keep on running.I think it's the wicking effect or something like that.Correct me if I'm wrong but I don't see a problem if it's running ok.
