when you get it replaced use either 60 thousands wire or a nylon strap fastened to the mounting area by the engine and wrapped around the second half of the muffler where the exhaust is. the reason they come apart is the center bolt comes loose and vibrates off. with safety wire or a nylon strap all you will lose is the center bolt and that is easier to find than the back half of a muffler. I had the same thing happen to me and started safety wiring the sections together.