94 f-250 7.3 IDI. When I use the midship tank on my truck, the fuel gauge always shows completely empty, no matter how much fuel is in it. I don't think its a fuel gauge issue, when I use the rear tank it reads normal. So is it a sending unit issue, or a float issue? When I park my truck overnight and am using the mid tank, the gauge goes up to about half, but when I start it the needle goes back to E. If it is a sending unit issue, is it in the tank? Any opinions appreciated.