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Looking for aftermarket parts to modify or upgrade your 1990 GMC C3500 with valve seals? At Tunersports.com we carry a huge selection of the top name brand performance valve seal parts and accessories.
 IN STOCK - DROPSHIPS 501-16Fits: 11/32" Valve Stems / OE-Size Valve Guides (.400" Outer Diameter). Valves Seals keep unwanted oil from entering the combustion chamber through clearance in the valve guides. Use standard o-ring Seal retainer and oil splash shield. Requires no machining.... COMP Cams Valve Seals 11/32in O Ring 1988-1993 GMC C3500 Sierra / Sierra SLX 1988-1995 GMC C3500 Sierra SLE $34.74 |
 IN STOCK - DROPSHIPS 504-16Fits: 3/8" Valve Stems - OE-Size Valve Guides (.900" Outer Diameter). Valves Seals keep unwanted oil from entering the combustion chamber through clearance in the valve guides. Normally used when a larger-than-stock diameter spring is used. Requires no machining.... COMP Cams Valve Seals 3/8in UmBRella 1988-1993 GMC C3500 Sierra / Sierra SLX 1988-1996 GMC C3500 Sierra SLE $42.23 |
 IN STOCK - DROPSHIPS 504-1Fits: 3/8" Valve Stems - OE-Size Valve Guides (.900" Outer Diameter)Valves Seals keep unwanted oil from entering the combustion chamber through clearance in the valve guidesNormally used when a larger-than-stock diameter spring is usedRequires no machining.... COMP Cams Valve Seal 3/8in UmBRella 1988-1993 GMC C3500 Sierra / Sierra SLX 1988-1996 GMC C3500 Sierra SLE $27.01 |