FP Increase your LB7?s potential with this simple, but effective upgrade. Back-to-back dyno pulls showed an increase of 15hp with this Fleece Performance Modified LB7 Intake Horn ? that?s about the cheapest 15hp from a bolt on you?ll find anywhere! Inexpensive horsepower upgrade solution for LB7. Back-to-back dyno pulls showed an increase of 15hp Fitment: 2001 Chevrolet Silverado 2500 HD Base 2001 Chevrolet Silverado 2500 HD LS 2001 Chevrolet Silverado 2500 HD LT 2001 Chevrolet Silverado 3500 Base 2001 Chevrolet Silverado 3500 LS 2001 Chevrolet Silverado 3500 LT 2001 GMC Sierra 2500 HD SL 2001 GMC Sierra 2500 HD SLE 2001 GMC Sierra 2500 HD SLT 2001 GMC Sierra 3500 SL 2001 GMC Sierra 3500 SLE 2001 GMC Sierra 3500 SLT 2002 Chevrolet Silverado 2500 HD Base 2002 Chevrolet Silverado 2500 HD LS 2002 Chevrolet Silverado 2500 HD LT 2002 Chevrolet Silverado 3500 Base 2002 Chevrolet Silverado 3500 LS 2002 Chevrolet Silverado 3500 LT 2002 GMC Sierra 2500 HD Base 2002 GMC Sierra 2500 HD SL 2002 GMC Sierra 2500 HD SLE 2002 GMC Sierra 2500 HD SLT 2002 GMC Sierra 3500 Base 2002 GMC Sierra 3500 SL 2002 GMC Sierra 3500 SLE 2002 GMC Sierra 3500 SLT 2003 Chevrolet Silverado 2500 HD Base 2003 Chevrolet Silverado 2500 HD LS 2003 Chevrolet Silverado 2500 HD LT 2003 Chevrolet Silverado 3500 Base 2003 Chevrolet Silverado 3500 LS 2003 Chevrolet Silverado 3500 LT 2003 GMC Sierra 2500 HD Base 2003 GMC Sierra 2500 HD SLE 2003 GMC Sierra 2500 HD SLT 2003 GMC Sierra 2500 HD WT 2003 GMC Sierra 3500 Base 2003 GMC Sierra 3500 SLE 2003 GMC Sierra 3500 SLT 2004 Chevrolet Silverado 2500 HD Base 2004 Chevrolet Silverado 2500 HD LS 2004 Chevrolet Silverado 2500 HD LT 2004 Chevrolet Silverado 2500 HD WT 2004 Chevrolet Silverado 3500 Base 2004 Chevrolet Silverado 3500 LS 2004 Chevrolet Silverado 3500 LT 2004 Chevrolet Silverado 3500 WT 2004 GMC Sierra 2500 HD Base 2004 GMC Sierra 2500 HD SLE 2004 GMC Sierra 2500 HD SLT 2004 GMC Sierra 2500 HD WT 2004 GMC Sierra 3500 Base 2004 GMC Sierra 3500 SLE 2004 GMC Sierra 3500 SLT 2004 GMC Sierra 3500 WT