The main purpose of exhaust packing wool is to reduce noise and control the temperature of the exhaust gases. Inside a muffler or exhaust system, the packing material is layered or tightly packed to create a barrier that absorbs and muffles the sound waves generated by the engine exhaust. This helps to reduce the overall noise level emitted by the vehicle or machinery.

In addition to its noise reduction properties, exhaust packing wool also serves as insulation to handle the high temperatures generated by the exhaust system. It helps to keep the heat inside the exhaust pipes, preventing excessive heat from radiating to the surrounding components or surfaces. This can protect sensitive parts from heat damage and help maintain optimal performance of the exhaust system.

Exhaust packing wool is commonly found in mufflers, resonators, catalytic converters, and other components of the exhaust system. Over time, the packing material may deteriorate or become compacted, which can reduce its effectiveness. In such cases, it may need to be replaced to restore the proper functioning of the exhaust system and maintain acceptable levels.