Dayco 70651 Radiator Coolant Hose - Upper

Dayco Curved Radiator Hose 70651

Dayco 70651 is a curved radiator coolant hose built for upper cooling-system routing on select GM and Pontiac applications. Made from EPDM rubber with a black finish, it uses a single I.D. hose design with 1 1/2-inch inside diameter ends for a direct replacement-style service part.

This Dayco Curved Radiator Hose line is focused on dependable coolant transfer and OE-style fitment for vehicles that need a formed upper hose with the correct bend profile. The 70651 part number is used across multiple classic Buick, Oldsmobile, and Pontiac applications, including Pontiac Grand Prix, Pontiac LeMans, and Pontiac Firebird models.

Key Features

• EPDM construction for cooling-system hose service
• Curved radiator coolant hose design for upper hose routing
• 1 1/2-inch inside diameter at both ends
• Single I.D. hose configuration
• Black exterior finish
• Built to SAE J20R4 Class D-1 and SAE J1684 Type EC specifications
• Dayco part number 70651 for catalog and cross-reference lookup

Detailed Description

Dayco 70651 is a formed upper radiator hose engineered for vehicles that require a curved coolant hose with matching inlet and outlet sizing. The EPDM rubber construction is suited for engine cooling-system temperatures and coolant exposure, while the molded shape helps maintain the proper hose path in the engine bay. This makes it a practical replacement for classic Buick Century, Pontiac Grand Prix, and Pontiac Firebird cooling-system service, as well as other listed Buick, Oldsmobile, and Pontiac models.

This part cross-references Gates 20710 for the same application. The Dayco 70651 radiator hose is also referenced by multiple OE and aftermarket numbers, making it easier to match during parts lookup and restoration work.

What It Helps Address

• Upper radiator hose leaks from age, cracking, or hardening
• Coolant loss caused by split or weakened hose walls
• Improper hose routing from a missing or damaged formed hose
• Cooling-system service on classic Buick, Oldsmobile, and Pontiac vehicles
• Replacement of a worn curved coolant hose with the correct 1 1/2-inch I.D. ends

Installation Notes and Tips

• Verify the hose shape and end diameters against the original part before installation.
• Inspect hose clamps, thermostat housing, radiator necks, and nearby fittings for corrosion or damage.
• Drain coolant to a safe level before removing the existing upper hose.
• Route the hose without twisting so the formed curve matches the engine bay layout.
• After installation, refill and bleed the cooling system according to the vehicle service procedure.

Quality Assurance

Dayco manufactures this hose to SAE J20R4 Class D-1 and SAE J1684 Type EC specifications for cooling-system hose applications. The 70651 part number is a cataloged replacement for select upper radiator hose applications across Buick, Oldsmobile, and Pontiac vehicles.

Vehicle Fitment

• Fits 1979 Buick Century, Upper
• Fits 1977-1979 Buick LeSabre, Upper
• Fits 1979 Buick Regal, Upper
• Fits 1979 Oldsmobile Delta 88, Upper
• Fits 1975 Oldsmobile Delta 88, Upper
• Fits 1971-1979 Pontiac Bonneville, Upper
• Fits 1971-1979 Pontiac Catalina, Upper
• Fits 1978-1979 Pontiac Grand Am, Upper
• Fits 1973-1975 Pontiac Grand Am, Upper
• Fits 1979 Pontiac Grand LeMans, Upper
• Fits 1975-1977 Pontiac Grand LeMans, Upper
• Fits 1971-1979 Pontiac Grand Prix, Upper
• Fits 1979 Pontiac LeMans, Upper
• Fits 1971-1977 Pontiac LeMans, Upper
• Fits 1976-1977 Pontiac Laurentian, Upper
• Fits 1971-1974 Pontiac Laurentian, Upper
• Fits 1976-1977 Pontiac Parisienne, Upper
• Fits 1971-1974 Pontiac Parisienne, Upper
• Fits 1975-1976 Pontiac Firebird, Upper
• Fits 1971-1972 Pontiac Firebird, Upper
• Fits 1975 Oldsmobile 98, Upper
• Fits 1975 Oldsmobile Custom Cruiser, Upper
• Fits 1971-1973 Pontiac GTO, Upper