Tire Tread/belt problems of the 2004 Toyota Tundra

Hi, I have (5) original equipment bf goodrich rugged trail,(p265/70r16), radial tires on my 2002 Toyota Tundra pickup truck that have 6,700 miles on them. At approximately 4,500 miles the tires started developeing cracks between the tread of each tire and only got considerably worse with passing time and miles. I contacted bf goodrich which told me to take the vehicle for inspection to a dealer that told me it would cost me almost $200 dollars to have the tires replaced and the other dealer said it would cost well over two hundred dollars for replacement. This second dealer told me I should not have to operate my vehicle with the current and deteriorating condition of these tires. I called bf goodrich back with the results of my dealer inspections, and basically they said what the delaler says, stands. These tires were obviously defective from the bf goodrich factory and I feel that it is only a matter of time before one fails, and blows out while I am traveling down the highway. I do not want to have another firestone atx situation affecting my safety or my passengers safety. I also believe that there are several other owners of these tires that may be subjected to the same tire failure risks that I am under. Thanks in advance, john m. Melnick.