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Looking for aftermarket parts to modify or upgrade your 1978 GMC C15 with exhaust gaskets? At Tunersports.com we carry a huge selection of the top name brand performance exhaust gasket parts and accessories.
 SHIPS FROM MANUFACTURER C5897CDesigned for extreme cylinder pressures... Cometic Chevrolet Mark-IV GM Gen-V/VI Big Block V8 .043in Copper Exhaust Manifold Gasket 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $71.14 |
 SHIPS FROM MANUFACTURER C5897HTGCometic's HTS Gaskets feature a graphite/fiber blend mechanically bonded to a perforated stainless steel core... Cometic Chevrolet Mark-IV GM Gen-V/VI Big Block V8 .094in HTG Exhaust Manifold Gasket Set 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $59.03 |
 IN STOCK - LOW C5897HTSCometic's HTS Gaskets feature a graphite/fiber blend mechanically bonded to a perforated stainless steel core... Cometic Chevrolet Mark-IV GM Gen-V/VI Big Block V8 .060in HTS Exhaust Manifold Gasket Set 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $51.16 CLEARANCE VIEW PRICE IN CART |
 SHIPS FROM MANUFACTURER C5996-030MLS Gaskets are comprised of multiple embossed layers of both AMP (Advanced Multi-Polymer Coating) and uncoated stainless steel... Cometic Chevy Mark-IV-GM Gen-V/VI Big Block V8 .030in MLS Exhaust Mani Gskt Set-2.130in Round Ports 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $72.12 |
 SHIPS FROM MANUFACTURER CP5251Cometic's HTS Gaskets are designed using reinforced gasket material compounds like armor-clad, graphite, and galvanized steel... Cometic Chevy Gen-4 Big Block V8 .060in HTS Exhaust Manifold Gasket - 2.250in Round Port - 20 Pack 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $201.03 |
 IN STOCK - DROPSHIPS 95021SGMAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Chevy 396 Performance Exhaust Manifold 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $95.46 |
 IN STOCK - DROPSHIPS 95100SGMAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Chevy 396 Performance Exhaust Manifold 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $86.27 |
 SHIPS FROM MANUFACTURER B7354MAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Buick Apollo 75-73 Intake To Exhaust Hot Spot 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $33.37 |
 IN STOCK - DROPSHIPS F7135MAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Chevrolet 3A 59 Exhaust Pipe Flange Gasket 1975-1978 GMC C15 Base $34.54 |
 IN STOCK - DROPSHIPS F7139MAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Checker Marathon 69-65 Exhaust Pipe Packing Ring 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $32.98 |
 IN STOCK - DROPSHIPS F7192MAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Chevrolet C10 Pickup 69-68 Exhaust Pipe Flange Gasket 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $34.88 |
 IN STOCK - DROPSHIPS F7207MAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Buick Apollo 75 Exhaust Pipe Packing Ring 1978-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande / Street Coupe $39.51 |
 OUT OF STOCK G26748MAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Buick Century 80-77 Exhaust Gas Recirculation Valve Gasket 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $33.32 |
 IN STOCK - DROPSHIPS MS15141MAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Buick Apollo 75 Exhaust Manifold Set 1978-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande / Street Coupe $42.56 |
 OUT OF STOCK MS15164MAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Chevrolet Bel Air 67-65 Exhaust Manifold Set 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $42.21 |
 IN STOCK - DROPSHIPS MS15750MAHLE(R) gaskets provide world class sealing products trusted by OEMs & Technicians around the globe.... MAHLE Original Buick Apollo 75 Exhaust Manifold Set 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $53.14 |