Dayco 70648 Radiator Coolant Hose - Lower

Dayco 70648 Curved Radiator Hose

Dayco 70648 is a curved lower radiator coolant hose for select Buick, Chevrolet, Oldsmobile, and Pontiac applications. Built from EPDM rubber with a 1 1/2 in. inside diameter at both ends, it provides a direct-fit cooling system hose solution for vehicles that need a curved lower hose layout.

The Dayco Curved Radiator Hose line focuses on OE-style hose routing and material selection for cooling system service. This 70648 hose follows the curved lower hose shape used on applications such as the Buick Skyhawk, Chevrolet Monza, Oldsmobile Starfire, and Pontiac Sunbird, helping maintain proper coolant flow and fitment in the engine bay.

Key Features

• EPDM construction for cooling system use
• Black finish for a clean OE-style appearance
• 1 1/2 in. inside diameter at both ends
• Single I.D. hose design
• Curved lower radiator hose profile
• Built to SAE J20R4 Class D-1 and SAE J1684 Type EC specifications
• Fits lower hose applications on select 1971-1980 Buick, Chevrolet, Oldsmobile, and Pontiac models

Detailed Description

Dayco 70648 is a radiator coolant hose for lower hose routing on a wide range of classic GM compact and intermediate vehicles. It fits applications including 1971-1976 Buick LeSabre and Riviera, 1973-1974 Buick Century and Regal, 1971 Buick Skylark, 1975-1976 Buick Skyhawk, 1975-1976 Oldsmobile Starfire, 1976 Pontiac Sunbird, and 1971-1980 Buick Skyhawk, Chevrolet Monza, Oldsmobile Starfire, and Pontiac Sunbird configurations listed in the fitment data. This part number, 70648, is also cross-referenced with Gates 20919 for the same application.

As a curved lower radiator hose, this part is used where the cooling system requires a formed hose to connect the engine and radiator without kinking or collapsing under normal service conditions. The EPDM material and SAE-rated construction support routine coolant circulation in vehicles that use a 1 1/2 in. hose connection at both ends.

Common Uses

• Replacing a cracked or hardened lower radiator hose
• Restoring coolant flow in a leaking cooling system
• Correcting hose fitment on curved lower hose routing
• Addressing swelling, soft spots, or coolant seepage at the hose ends
• Servicing classic Buick Skyhawk, Chevrolet Monza, Oldsmobile Starfire, and Pontiac Sunbird cooling systems

Installation Notes and Tips

Verify the lower hose routing, end diameters, and vehicle configuration before installation. This hose is listed for both air-conditioned and non-air-conditioned applications on certain 1977-1980 Buick Skyhawk, Chevrolet Monza, Oldsmobile Starfire, and Pontiac Sunbird models, so match the exact fitment notes to the vehicle. Inspect hose necks, clamps, and adjacent cooling system components before installing the new hose.

Quality Assurance

Dayco manufactures this hose to SAE J20R4 Class D-1 and SAE J1684 Type EC requirements, supporting consistent material and dimensional standards for cooling system service.