In 2008 I installed two 40 series Glow Masters on my 03' F150 (4.6). I've spent a lot of money dropping one and rusting through the other, both this year. I decided I needed the same sound but with less cab resonance so I replaced two separate mufflers with this 2 in 2 and couldn't be happier with the sound and performance of this muffler on my pickup. It was also half the cost of the last joke.