Pull the tank. It is easy enough.
Behind the tail light on the driver's side. That's on a '56. The center section of the the tailfin chrome on the driver's side swings out and the gas cap is there on a '57.
just keep driving. when it stops, you're empty.
The fuel sensor in the gas tank is bad.
bad sending unit
The sending unit is probably bad, not unusual.
inertia
FORD
30 GAL. when compleatly empty.
Bad fuel level sending unit.It is located in gas tank.Tank must ne dropped to replace.Can get units from local auto parts stores.
You will have to remove the tank and then remove the fuel sending unit and then empty the tank. NO OTHER WAY.
unfortunately the Chevy venture is known for have many of the sensors going bad. I have a 2000 Chevy Venture that gives the wrong readings for everything. I never know where my gas level is until it is actually 'empty'.
THIS is Not precise but I own a 2003 Tahoe. I would say 22-24 Gallons. From Reasonably Empty.