Thanks, I suspect the factory did not torque them in the right sequence or with the right value, standing by my driver door and looking at them, the seem on the bottom right one is bent a little. I know about the heat issue from the engine which could be a contributor but I also think torqued improperly could be a potential issue also. BTW, I just replaced the factory muffler, but I was thinking of loosening them and re-torquing them to 9 inch/lbs properly, or should I leave well enough alone :confused., and no I'm not taking her to the dealer for the repairs.