Mufflers need replacement if they get rusty or develop holes. The primary reason for replacing most mufflers is that they are no longer functional. This period of time varies greatly. Mufflers typically last ten years. However, the service life might vary from five to fifteen years depending on a number of variables, including exposure to moisture such as rain, snow, and salt. Unfortunately, in regions with severe weather and driving conditions, a subpar optional accessory muffler could only last three years.