The fuel level sender can malfunction causing the fuel gauge to always read at the full level.
Average mileage: 82,500 (37,000–130,000)
Electrical & Lights affected: 4.2L 6 Cylinder, 5.3L V8
18 people reported this problem
The low fuel light will stay on along with the engine light, no matter how much fuel is in the tank. Every once in awhile in a sharp turn or steep hill it will give me a reading of what is actually in the tank but only for a split second.
I pull into the gas station without the fuel light on, then I leave the gas pump after putting 20 gallons in it and the low fuel light is on as well as the check engine light. I was reading on line that GM is taking care of half the cost of the fuel pump/sending unit / sensor as it is all one part.