How ofter do you need to replace a muffler in a newer car?

Most mufflers last as long as you will own your new car. The most common reason for replacing a muffler today is due to an accident or corrosion. In harsh climates, a muffler may need to be replaced every 10 or 15 years.

It all depends on how often you drive and how far you drive. If you drive it every day then you might want to change it after 2 years.