SLP Exhaust System, 2004-08 F-150 4.6/5.4 LoudMouth II Side Exit.
Fits: Ford 2004-06 F150 4.6/5.4 Super Cab 6.5 Bed/Super Crew 5.5 Bed
It offers up to 10 extra horsepower and 10 foot-pounds of torque with an aggressive muscle-car rumble you'll really like. The secret to the system's distinctive sound is a pair of stainless steel Loud Mouth II resonators, highly polished and stamped with the SLP logo. The additional performance comes from the free-flow design. The system features a pair of attractive 3.5 dual-wall stainless steel tips that look great peeking out of the passenger side. The modular design gives you flexibility to change to a more aggressive sound in minutes by purchasing a pair of bolt-in Loud Mouth bullet-style resonators (#31062). The exhaust system is hand-crafted from 2.5 stainless steel, and is covered by our Limited Lifetime Warranty. Loud Mouth II Side Exit catalyst-back exhaust system for 2004-06 Ford F150 features:
Limited Lifetime Warranty
Aggressive muscle-car rumble
Modular design lets you bolt-in a pair of Loud Mouth resonators (#31062, not included) for a louder system
Hand-crafted from stainless steel
Easy bolt-on installation
Distinctive stainless tips that rotate for the look you want
Applications:
2004 - 2008 Ford Trucks
SLP Exhaust Type Descriptions/Definitions/Details: (use as a guide to the exhaust system on this page for details about the muffler type.)
Model
Type
Sound Characteristics*
Noise Level*
Bullet-Type Open Resonator (or muffler delete)
Extremely aggressive; powerful high- and mid-range tones with
moderate resonance
Muffling, Bullet- Type Resonator
Similar to original Loud Mouth, but with a throatier tone and reduced
resonance
Straight-Through "Traditional" Muffler
Deep, rich, and mellow; minimal resonance
*
Volume and sound quality will vary based on engine and exhaust-system
specifications. Loudmouth also refers to some systems without any resonators such as the 2010 Camaro Loud Mouth and the 2005 Mustang Loud Mouth Axle backs where the mufflers are removed altogether. Images below are representations in order to better understand the differences.
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