'02 Z71 Gas Gauge Prob

I recently purchased a 2002 Z71 Tahoe that is in great condition, has 36,000 miles and I have a small problem. The gas gauge doesn't seem to be very accurate, when I get to 270mi on my odometer the tank still reads about 75% full (I get about 340mi/full tank), as the mileage increases the gauge slowly decreases until I reach about 295-300 and then it drops quickly down to "E" and my low fuel indicator comes on.

My car was sitting around unused for about 2-3 months beforehand and I suspect this has something to do with it. Does anybody know if this will go away or I can buy a fuel additive to "unstick" the gauge? I don't want to spend money for a small repair if there is a quick fix. Thanks.

Read the post I just made on GM Fuel Pumps. The metal in the fuel pump corrudes causing stalling and fuel gauges stick then drop, etc. The corrision causes the fuel sensor to not read properly. The girl at the dealership had the same problem as you and her problem was also the fuel pump. Hope this helps, good luck.

It is the sending unit in the tank, But the sending unit and pump came as one unit and are $300.00 + just for the part.

Thanks for all your help!!