Other Fuel System Tank Mounting problems of the 2001 Chevrolet S10

Gas gauge in my truck has been erratic since day 1. I have brought it back to the dealership numerous amounts of time. I thought it was lack of knowledgement from the dealership so I brought it to another gm service garage and they told me becasure of the design of the gas tank they would not be able to fix the problem. I have run out of gas twice and almost had a serious accident once. The needle reads fine u7ntil it reaches 1/4 of a tank and then it drops to empty and then you are on your own. When driving down the highway and the needle reaches 1/4 of a tank the needle doesn't move until you come to a stop and then it drops to empty and the gas gauge doesn't come on to let you know that you are low on gas. I have had it with this truck and the dealership. Please help !!! I let the 1st dealership take my truck and drivie it because they said that they couldn't duplicate the same problem they put 400 miles on my truck and said that the gas gauge didn't do what I was saying. I drove it out of their yard and went 15 miles and the truck did what I was saying it was doing. I think that I have been more than patient with this garage.