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1999-2004 Mustang GT/Mach 1 LoudMouth II Exhaust System

Free Shipping Price: $639.99 (USD)
Part #: M31007A
LoudMouth's Mustang Cat-Back Exhaust Systems have always been the best performing exhaust systems in the business. Now they're the most versatile, too! Using groundbreaking modular technology first seen on our Mustang X-pipes, we've developed a line of systems that can be quickly reconfigured to fit changing performance, noise level, and sound quality requirements. Simply loosen a few band clamps, swap muffler types, re-tighten, and you're done. No other exhaust offers this level of performance and adaptability!

Along with the included race mufflers, the LoudMouth II® system is compatible with our original resonators (#31062) and our all new, straight-through type PowerFlo® traditional mufflers (#31065). Buy all three for complete control over your Mustang's sound and performance characteristics.

NOTES: Includes SLP race mufflers. SLP resonators and PowerFlo traditional mufflers sold separately.

  • Includes SLP bullet-type race mufflers for minimal restriction, reduced resonance, and an aggressive tone
  • Employs LoudMouth's exclusive modular technology, making it possible to switch between muffler and resonator types in a matter of minutes
  • Engineered and built to OEM standards to ensure proper fit
  • Constructed entirely from mandrel-bent stainless steel
  • Features show quality polished mufflers and 3.5" double-wall tips with elektromarked SLP logo
  • For 1999-2004 GT and Mach I models

WARNING: Cancer and Reproductive Harm -
  • Mustang GT, Mach 1 - 1999, 2000, 2001, 2002, 2003, 2004
  • Install Hours: 1.5
  • Tools: Shop Tools
  • Install Difficulty: Intermediate

SLP M31007A Loud Mouth II Exhaust Instructions