🚗 Flowmaster 843048 Super 409S Muffler Review

This muffler transformed my truck into a quiet beast. As a result of using this product, I found that my vehicle had much improved flow and performance without sounding like a jet engine. The 409S stainless steel construction is incredibly durable, and it looks great. The only con is that it may be a bit pricey for those on a tight budget. Overall, an excellent upgrade for any truck owner.

After installation I started the truck for the first time and was concerned that my muffler wasn't quiet enough for the cop next door. To me it sounded the same as with open pipes. Then, as I drove around town, I could tell that it limited noise levels and cut out harsh high-pitched sounds. Perfect. It sounds like open pipes at idle but is reassured by harder acceleration.

Comparing the sound of my 11 Mustang GT to these sounds, I have no doubt that the amount of subtle tones my car resonates with is anything but quiet. I've always loved FM and their lines turning them off. Now with LT fans, off-road X-pipe, resonator removal, 3" stainless steel over my FM Super 44s, they sound even more amazing. I received a strong compliment from another 11 GT owner who rode a Borla all the way back drove (minus the headlines and his X-pipe) who stated my car sounded better…