Dayco 71903 Radiator Coolant Hose - Upper

Dayco 71903 Curved Radiator Hose

The Dayco 71903 curved radiator hose is a black EPDM upper coolant hose built for specific Ford and Mercury applications. It is shaped as a single I.D. hose with 1 1/2-inch inside diameter ends to match the cooling system routing on select Explorer and Mountaineer models.

Compatible With 1996-2001 Ford Explorer, upper, and 1997-2001 Mercury Mountaineer, upper. This Dayco Curved Radiator Hose line focuses on direct-fit cooling system hose replacement for vehicles that need the correct bend, diameter, and material specification for upper radiator routing.

Key Features

• EPDM construction for coolant hose service
• Black finish for OE-style appearance
• 1 1/2-inch inside diameter at both ends
• Single I.D. hose design for upper radiator routing
• Built to SAE J20R4 Class D-1 and SAE J1684 Type EC specifications
• No heat shield or protective sleeve included

Detailed Description

Dayco 71903 is a curved radiator coolant hose engineered for upper hose applications on the Ford Explorer and Mercury Mountaineer. The EPDM rubber construction is selected for cooling system use, while the curved profile helps maintain the proper hose path between engine and radiator connections. The 1 1/2-inch end diameters and single I.D. hose layout support a direct replacement approach for vehicles that require this specific hose shape and size. This part cross-references Ford (e.g., F67A-8B274-HA, F67Z-8260-GA) for the same application.

Fits 1996-2001 Ford Explorer, upper. Fits 1997-2001 Mercury Mountaineer, upper. If you are searching for a Dayco 71903 radiator hose for Ford Explorer upper hose replacement or a Mercury Mountaineer curved coolant hose, this part matches the listed applications and specifications.

Common Problems This Hose Can Address

• Cracked or split upper radiator hose
• Coolant leaks at the hose body or connection points
• Softening, swelling, or deterioration from heat and age
• Incorrect hose routing after a failed replacement
• Loss of cooling system integrity from a worn coolant hose

Installation Notes and Tips

Verify the hose diameter, routing, and upper position before installation. Inspect the radiator neck, engine outlet, and clamps for wear or corrosion, and replace any damaged sealing surfaces as needed. Confirm that the hose follows the original curved path without kinks or twist before refilling and bleeding the cooling system.

Quality Assurance

This Dayco Curved Radiator Hose is manufactured to SAE J20R4 Class D-1 and SAE J1684 Type EC specifications for radiator coolant hose service. Its EPDM material and application-specific shape support consistent fitment on the listed Ford Explorer and Mercury Mountaineer models.