Gates 21045 Radiator Coolant Hose - Upper

Gates 21045 Molded Coolant Hose Overview

Gates 21045 is a molded radiator coolant hose built for upper coolant routing on select Ford trucks and SUVs from 1977-1979. It uses EPDM construction and molded OE-style shaping to match the factory hose path for a cleaner, more direct replacement.

Compatible with Ford Bronco, F-100, F-150, F-250, and F-350 upper hose applications, this Gates molded coolant hose is made for service work where correct fit and routing matter. The Gates Molded Coolant Hose line covers upper, lower, bypass, heater, and other coolant applications with OEM-quality specifications.

Key Features

• Part number: 21045
• Brand line: Gates Molded Coolant Hose
• EPDM rubber construction for coolant system use
• Molded design for factory-style hose routing
• End 1 inside diameter: 1.5 in. (38 mm)
• End 2 inside diameter: 1.75 in. (44 mm)
• Centerline length: 15.4 in. (391 mm)
• No spring and no quick-connect fittings

Detailed Description

Gates 21045 is a molded radiator coolant hose for upper hose service on 1977-1979 Ford Bronco, F-100, F-150, F-250, and F-350 applications. The molded shape helps maintain the original hose path, while the EPDM material is suited for coolant system temperatures and long-term underhood use. This part number is a direct-fit style replacement for vehicles that require the specified inlet and outlet diameters and centerline length.

This part cross-references Gates 41041 and Dayco 70871 for the same application. If you are replacing a worn upper radiator hose on a 1978 Ford Bronco or a 1979 Ford F-150, Gates 21045 provides the correct molded configuration for the factory routing.

Common Problems This Hose Can Address

• Cracked or split upper radiator hose
• Coolant leaks at the hose body or ends
• Collapsed or softened hose material
• Poor hose routing after a previous replacement
• Overheating caused by restricted coolant flow

Installation Notes and Tips

Verify the hose shape, end diameters, and centerline length before installation. Confirm upper hose routing on the vehicle and inspect the radiator neck and engine connection points for corrosion, scale, or old clamp residue. Replace clamps if wear or damage is present, and make sure the hose is seated fully before refilling the cooling system.

For fitment reference, this hose fits 1978-1979 Ford Bronco, upper; 1977-1979 Ford F-100, upper; 1979 Ford F-100, upper; 1977-1979 Ford F-150, upper; 1978-1979 Ford F-150, upper; 1977-1979 Ford F-250, upper; 1978-1979 Ford F-250, upper; 1977-1979 Ford F-350, upper; and 1978-1979 Ford F-350, upper.

Quality Assurance

Gates manufactures molded coolant hoses to OEM-quality specifications and offers one of the broadest replacement hose lines in the aftermarket. That focus on fitment coverage and molded construction supports accurate replacement for Ford Bronco, F-100, F-150, F-250, and F-350 cooling system service.