08 F150 5.4 Flex Fuel I wasn't sure about this muffler because it's not a common name. When I installed it I was very impressed with the sound. Haven't tried it on the freeway yet, but it sounds great around town. It has a nice rumble, it's not a loud head spinning noise, which I didn't want. If it wears out or rusts I will buy it again * Installed it in my shed in about an hour.