You may not know it, but the factory drivers side exhaust manifold is pinched down to allow for steering shaft clearance, which actually is not required. As a result, thismanifold only flows 80-percent of the passenger side. BDs Full Bore exhaust manifoldrestores exhaust flow balance, improving power and reducing EGT. Made from high silicon ductile iron, the Full Bore is a direct, bolt-in replacement for the factory manifold and is even drilled and tapped to accept the most popular EGT probes.
Installation Instructions


This Part Fits:

Year	Make	Model	Submodel
2001-2005	Chevrolet	Silverado 2500 HD	Base
2001-2006	Chevrolet	Silverado 2500 HD	LS
2001-2010	Chevrolet	Silverado 2500 HD	LT
2007-2010	Chevrolet	Silverado 2500 HD	LTZ
2003-2010	Chevrolet	Silverado 2500 HD	WT
2007	Chevrolet	Silverado 2500 HD Classic	LS
2007	Chevrolet	Silverado 2500 HD Classic	LT
2007	Chevrolet	Silverado 2500 HD Classic	WT
2001-2005	Chevrolet	Silverado 3500	Base
2001-2006	Chevrolet	Silverado 3500	LS
2001-2006	Chevrolet	Silverado 3500	LT
2004,2006	Chevrolet	Silverado 3500	WT
2007	Chevrolet	Silverado 3500 Classic	LS
2007	Chevrolet	Silverado 3500 Classic	LT
2007	Chevrolet	Silverado 3500 Classic	WT
2007-2010	Chevrolet	Silverado 3500 HD	LT
2007-2010	Chevrolet	Silverado 3500 HD	LTZ
2007-2010	Chevrolet	Silverado 3500 HD	WT
2002-2005	GMC	Sierra 2500 HD	Base
2001-2002,2006	GMC	Sierra 2500 HD	SL
2001-2010	GMC	Sierra 2500 HD	SLE
2001-2010	GMC	Sierra 2500 HD	SLT
2003-2010	GMC	Sierra 2500 HD	WT
2007	GMC	Sierra 2500 HD Classic	SL
2007	GMC	Sierra 2500 HD Classic	SLE
2007	GMC	Sierra 2500 HD Classic	SLT
2007	GMC	Sierra 2500 HD Classic	WT
2002-2005	GMC	Sierra 3500	Base
2001-2002,2006	GMC	Sierra 3500	SL
2001-2006	GMC	Sierra 3500	SLE
2001-2006	GMC	Sierra 3500	SLT
2004-2006	GMC	Sierra 3500	WT
2007	GMC	Sierra 3500 Classic	SL
2007	GMC	Sierra 3500 Classic	SLE
2007	GMC	Sierra 3500 Classic	SLT
2007	GMC	Sierra 3500 Classic	WT
2007-2010	GMC	Sierra 3500 HD	SLE
2007-2010	GMC	Sierra 3500 HD	SLT
2007-2010	GMC	Sierra 3500 HD	WT