MagnaFlow has a variety of 2003 GMC Sierra 3500 catalytic converters that meet California Grade, HM Grade or OEM Grade requirements. Keep your large pickup’s check engine light off with one of these high-flow converters. Each converter features durable stainless-steel construction and utilizes either a direct-fit or universal design compatible with Base to SLT trim levels equipped with engine options ranging from the 6.0L CNG V8 to the 8.1L gas V8. Select your ‘03 GMC Sierra 3500’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 3500 replacement exhaust system? Shop all BRExhaust 2003 GMC Sierra 3500 Direct-Fit Replacement Exhaust Systems to find the best aftermarket kit to replace your 2003 GMC Sierra 3500 OEM exhaust.

MagnaFlow offers complete performance exhaust systems for your 2003 GMC Sierra 3500. Determine the power and sound you demand for your 2003 Sierra 3500 and shop all available exhaust systems online. Select your '03 GMC Sierra 3500 sub-model and engine details to buy the best exhaust system that fits your needs.