Sign up to receive info on new products, events, special offers and more!

2004-2006 GTO Parts & Accessories - Exhaust & Headers

SLP Loudmouth II Exhaust System - 2005-06 Pontiac GTO


Bolt on a Loud Mouth II modular catalyst-back exhaust system from SLP on your new 2005 GTO for up to 5 extra horsepower and 5 foot-pounds of torque with the aggressive musclecar rumble your LS2 deserves. Not quite as loud as our original Loud Mouth, the system's great sound comes from a pair of stainless bullet mufflers complete with embossed SLP logo. Our engineers developed a great sound for the street without objectionable in-cabin resonance. The additional performance comes from the free-flow design and our built-in PowerFlo-X Crossover system that borrows a power-building technique widely used in stock car racing. The system features a pair of distinctive 3.5" dual-wall stainless steel tips that look great peeking out of the GTO's rear valence. The tips have an angle cut and can angle downward in a traditional style, or rotated at a 90 degree angle so they match the curving shape of your rear valence. The modular design gives you flexibility to change to a louder system in minutes by purchasing a pair of bolt-in Loud Mouth resonators (#31062). The exhaust system is hand-crafted from 2.5" 304 stainless steel, and is covered with our Limited Lifetime Warranty.

Loud Mouth catalyst-back exhaust system for 2005 GTO features:

  • Limited Lifetime Warranty
  • Aggressive musclecar rumble, not as loud as our Loud Mouth system (#31560)
  • Modular design lets you bolt-in a pair of Loud Mouth resonators (#31062, not included) for a louder system
  • Hand-crafted from 304 stainless
  • Easy bolt-on that mounts to SLP's header system or stock exhaust
  • Distinctive stainless tips that rotate for the look you want