There are plenty of F150 5.0L exhaust kits that have a great sound, because, well, it's actually pretty hard to make these trucks sound bad. That being said, finding one with the awesome looks to set your F150 apart from the rest of the crowd with one of the most aggressive appearances on planet is a rare find indeed. That's where the Gibson Metal Mulisha® cat-back exhaust kit comes in. This big, bad 4" diameter cat-back system produces a great sound thanks to its performance muffler design and comes standard with an absolutely massive 6" diameter black ceramic exhaust tip that comes decked out in the Metal Mulisha® skull logo in silver. The kit has a big, tough look and gives your truck a clean, aggressive sound with practically no drone at idle or cruising. This is one kit that is sure to catch everyone's eye and we went ahead and got it installed on our 2012 F150 5.0L FX4 Project Truck.
Like most cat-back kits that have an OEM-style single side exit, installation of the Gibson Metal Mulisha® cat-back kit was pretty basic. The toughest part, at least for us, was finding our factory resonator pipe. All of the kits that we've installed and tested so far came with new intermediate tubing connecting our truck's mid-pipe to the muffler on our kits. Gibson's kit requires the stock pipe and resonator assembly for proper fitment, so that kit is technically a "resonator-back" system, rather than a complete cat-back. After we managed to find one, the install went very smooth. Naturally, our first step was to head down to Extreme Performance out in Goodyear, Arizona, where Chris was waiting to help us out.
So, if you're like us and you're coming over from a different F150 cat-back exhaust kit, make sure to find an OEM resonator pipe assembly for proper fitment of this kit.
If you have the factory cat-back kit installed on your truck, kit the clamps holding the muffler and resonator pipe together with some penetrating oil, let it soak for a few minutes, and then remove the muffler and over-axle tubing from your truck while working them from their hangars from your truck's mounts.
Now Chris took Gibson's muffler tube and slide its hangar through the stock mount and fit its necked-down end into the factory resonator tubing. He then supported the muffler on an axle stand.
Chris fit one of the included clamps over the muffler's outlet before maneuvering Gibson's over-axle tube over our truck's axle, through the upper bed rail mount, and into the muffler's outlet.
The over-axle tube also acts as the outlet and Chris needed to fit its hangar into the aft OEM exhaust mount while pushing it over the axle.
With all of the tubing in place, all Chris had to do was get the massive exhaust tip on and go back to tighten all the clamps.
With that, our Gibson Metal Mulisha® cat-back install was complete. The kit looks great, if maybe a little flashy. Soundwise, though, the system is pretty mellow with a decent roar when you're on the throttle, but barely a whisper at idle and low RPMs. Overall, it's a pretty good kit with excellent fitment. If you want a more ferocious sound, you could cut out the factory resonator or have a new pipe fabricated that completely deletes it.
