Problems with 2004 Chevrolet Monte Carlo TIRES

We purchased a 2004 chevy monte carlo ss @ jim johnson nissan here in bowling green,ky in december of 2006. since then we have been feeling a "thumping" while driving-no matter what speed. we had taken the car to jim johnson a couple of times, which tires were taken off-balanced and re-balanced and still the same issue. jim johnson had placed 2 new tires on the front but we are still having the same problem. the tires we have on there are goodyear eagles. we called goodyear consumer ctr. they in turn had us go to a goodyear tire dealer for a tire inspection, upon which they found a "thumping" in the tires. goodyear consumer center had offered us $58. for each tire replacement towards the warranty. we feel for our safety and others around our car,we shouldn't have to spend any money for replacement of the two tires that are faulty and defective, we feel that they should replace them at no charge to us for safety reasons and the idea that they are faulty and defective no matter what the warranty claims are. we feel they are not standing behind their product. *jb

Brakes grinding at 14,000 miles, 2 tires wearing. taken to dealer, dealer turned rotars and said tires were goodyears problem. taken to goodyear dealer,was told it was a bad set up by car dealer and was the 3rd car brought in from that dealer. called gm hot line and was told to take into another dealer and that we would have to pay for estimate if it wasn't warranty. the first told us it would not be warranty. now we are driving on an almost bald tire with my children and grandchild in the car. the reason we bought a new car is so we would have a safe car and when we spent 20,000 dollars we thought it would last more than a year not only 14,000 miles. after the dealer turned the left rear rotar it still has marks on it.