GM Service Manual Online
For 1990-2009 cars only

The exhaust muffler is used to reduce the noise levels of the engine exhaust by the use of baffles. The baffles in the exhaust muffler create channels inside the exhaust muffler that lower the sound levels created by the combustion of the engine. A resonator is mounted forward of the exhaust muffler also helps reduce noise levels. Exhaust system hangers and insulators support the weight of the muffler. The exhaust system hangers also space the muffler away from the underbody of the vehicle and allow for exhaust system expansion that occurs as the exhaust system warms up.