4 Wheel Drive/SUVs: fuel gauge on 1995 Silverado, fuel gauge, gm vehicles

Question
Hi,
The fuel gauge on our '95 Silverado, 4x4 diesel reads half full even though it is full. This morning it went from half down to 3/4 empty on the drive to town (30mi). I fueled up, it only took a few gallons,($10 to be exact) and the gauge was back at half. We haven't had this truck that long but we have fueled it several times and it always seemed to work properly. Any ideas? Thanks Judy. PS a while back you answered a question regarding the 4x4 indicator light on an Escalade we had and were right on the money. Thanks again!

Answer
Judy the Gm vehicles seem to always have trouble with their fuel gauges, It is most likely the sending unit that is in the fuel tank, Which is usually not a cheap fix the sending unit is more than likely $300 - $500 . So if you are good at keeping track of the miles I would say just keep driving it. Thanks alot and I wish all the best Happy early thanksgiving . ADAM