MagnaFlow has a variety of 2003 GMC Sierra 1500 catalytic converters that meet California Grade, HM Grade or OEM Grade requirements. Maintain your full-sized pickup’s emissions system and keep your truck road legal. Each converter features durable stainless-steel construction and utilizes either a direct-fit or universal design compatible Base to WT trim levels equipped with engines ranging from the 4.3L V6 to the 6.0L V8. Select your ‘03 GMC Sierra 1500’s specifications and state vehicle registration to ensure you buy the correct catalytic converter that fits your truck’s needs and meets your state’s emissions compliance regulations.

Need a 2003 GMC Sierra 1500 replacement exhaust system? Shop all BRExhaust 2003 GMC Sierra 1500 Direct-Fit Replacement Exhaust Systems to find the best aftermarket kit to replace your 2003 GMC Sierra 1500 OEM exhaust.

MagnaFlow offers complete performance exhaust systems for your 2003 GMC Sierra 1500. Determine the power and sound you demand for your 2003 Sierra 1500 and shop all available exhaust systems online. Select your '03 GMC Sierra 1500 sub-model and engine details to buy the best exhaust system that fits your needs.