Does a loud muffler waste gas?
loud muffler will not use more gas and a performance muffler such as a flowmaster will add a couple of horse to your vehicle and a muffler will last a long time if you do a lot of highway driving where it gets to burn all the moisture out of it but if you do short trip driving where you only drive a couple of miles the water in the exhaust doesn’t have a chance to get burnt out of the system and the muffler will rust off a lot sooner.