When i fill upa full tankthe needle goes over the FULL marker, as the tank empties the farthest the needle decreases is a little under the 3/4 FULL marker and no further.

I think its either the fuel pump sensor that is being obstructed somehow or the dashboard needle itself may be the problem.
Any ideas or suggestions are appreciated

 

Could be the in-tank fuel level indicator.....basically a float on an arm.

 

That is a typica GM fuel gage, not worth fixing it, just get used to it. Fill up when it reads 1/2 and you will have 3-4 gal cushion.

 

I have the same problem...just learn how many miles you can travel on a tank and keep reseting the trip meter when you fill up. I figured mine out because my trip meter said I had drove almost 300 miles and was reading at just under 3/4 of a tank. And I just new that wasnt right so I quickly found a gas station and filled up. With the amout of gas it took to fill it, I figured I was lucky, cuz I was most likely running on empty.

 

I figured my gas gage out after I ran out of gas twice. The third time doesn't count because I wasn't actually out of gas I was just really low. I run out of gas at a hair under 1/4 but get nervious enough to stop ANYWHERE at 1/2 tank. Needless to say the gas gage is my best friend these days.