Dayco 70637 Engine Coolant Bypass Hose

Dayco Curved Radiator Hose 70637

Dayco 70637 is a curved engine coolant bypass hose built for select Dodge, Chrysler, Plymouth, and Nissan applications. Made from EPDM rubber with a black finish, it uses a single I.D. hose design with 1-inch inside diameters at both ends for direct-fit cooling system service.

Key Features

• EPDM construction for coolant-system durability
• Curved radiator hose profile for routed engine bay fitment
• Single I.D. hose design with 1-inch end inside diameters
• Black finish for OE-style appearance
• Built to SAE J20R4 Class D-1 and SAE J1684 Type EC specifications
• Dayco Curved Radiator Hose line for cooling system replacement needs

Product Details

This Dayco Curved Radiator Hose is engineered as an engine coolant bypass hose for vehicles that require a formed hose shape and consistent coolant flow routing. The EPDM material is commonly used in cooling system service because it is suited to heat, coolant exposure, and long-term underhood use. Part number 70637 is listed across a wide range of classic and late-model applications, including Dodge D150, Dodge Dakota, Chrysler Fifth Avenue, and Nissan 300ZX.

This part cross-references Gates 20693 for the same application.

Used For

• Replacing a cracked or softened coolant bypass hose
• Restoring proper coolant routing in curved hose applications
• Addressing coolant leaks at hose connections
• Correcting hose collapse, swelling, or heat-related deterioration
• Servicing cooling systems on Dodge, Chrysler, Plymouth, and Nissan vehicles

Installation Notes and Tips

• Verify 1-inch inside diameter at both hose ends before installation.
• Inspect hose necks, clamps, and adjoining coolant passages for wear or corrosion.
• Match the curved routing to the original hose path to avoid kinks or tension.
• Confirm vehicle application by year, make, and model before ordering.
• Fits 1970-1974 Dodge Challenger, N/A; Fits 1970-1976 Dodge Dart, N/A; Fits 1970-1978 Dodge Charger, N/A; Fits 1971-1972 Chrysler Newport, N/A; Fits 1971-1978 Dodge Monaco, N/A; Fits 1971-1981 Chrysler Newport, N/A; Fits 1975-1977 Dodge W100, N/A; Fits 1975-1989 Dodge D100, N/A; Fits 1975-1980 Dodge B100, N/A; Fits 1975-1980 Dodge B200, N/A; Fits 1975-1980 Dodge B300, N/A; Fits 1975-1980 Dodge D200, N/A; Fits 1975-1980 Dodge D300, N/A; Fits 1975-1980 Dodge W200, N/A; Fits 1975-1980 Dodge W300, N/A; Fits 1975-1981 Chrysler Newport, N/A; Fits 1976-1980 Dodge Aspen, N/A; Fits 1977-1980 Chrysler New Yorker, N/A; Fits 1977-1981 Chrysler LeBaron, N/A; Fits 1977-1991 Dodge D150, N/A; Fits 1977-1991 Dodge W150, N/A; Fits 1978-1979 Dodge Magnum, N/A; Fits 1978-1981 Chrysler Town & Country, N/A; Fits 1981-1983 Chrysler Imperial, N/A; Fits 1981-1983 Plymouth PB150, N/A; Fits 1981-1983 Plymouth PB250, N/A; Fits 1981-1983 Plymouth PB350, N/A; Fits 1981-1991 Dodge B150, N/A; Fits 1981-1992 Dodge B250, N/A; Fits 1981-1992 Dodge B350, N/A; Fits 1981-1992 Dodge D250, N/A; Fits 1981-1992 Dodge D350, N/A; Fits 1981-1992 Dodge W250, N/A; Fits 1981-1992 Dodge W350, N/A; Fits 1982 Chrysler New Yorker, N/A; Fits 1983 Chrysler Fifth Avenue, N/A; Fits 1984-1989 Nissan 300ZX, N/A; Fits 1985-1989 Dodge D100, N/A; Fits 1986-1989 Dodge W100, N/A; Fits 1987-1988 Nissan 200SX, N/A; Fits 1987-1991 Dodge Dakota, N/A; Fits 1987-1992 Dodge B250, N/A

Quality Assurance

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