Muffler outer shell broken
If the muffler's outer shell is broken, the exhaust sound waves can escape before being muffled. Additionally, depending on where and how the shell is broken, it may affect the support parts and loosen the muffler.
Table of Contents
Muffler Makes a Rattling Noise
If the muffler is loose, it can sway back and forth during driving. As it hits other parts, it will produce a banging noise.
Damage to the muffler shell can also loose some of the interior parts. This will produce a rattle from within as the parts are tossed about by the movement of the vehicle.
Exhaust Abnormally Loud
As the sound waves travel through the muffler, they are diminished. If the waves can escape early in their travel through the muffler, the exhaust sound will be much louder than normal. If the damage to the shell occurs later on, such as toward the outlet, the sound waves may have been dampened significantly. This would create a slight increase in exhaust volume.