Dayco 71668 Radiator Coolant Hose - Lower, Lower - Radiator To Thermostat or Upper

Dayco Curved Radiator Hose 71668

Dayco 71668 is a curved radiator coolant hose built for specific Nissan Altima and Toyota T100 applications. Made from EPDM rubber and finished in black, it follows the routing needed between the radiator and thermostat on listed vehicles while meeting SAE J20R4 Class D-1 and SAE J1684 Type EC specifications.

The Dayco Curved Radiator Hose line is engineered for direct-fit cooling system service where a formed hose is required to maintain proper coolant flow and routing. This part number, 71668, is a single I.D. hose with matching 1 11/32-inch inside diameters at both ends for the listed applications.

Key Features

• EPDM construction for cooling system use
• Black curved radiator hose profile for formed routing
• 1 11/32-inch inside diameter at both ends
• Single I.D. hose design
• Meets SAE J20R4 Class D-1 and SAE J1684 Type EC specifications
• Direct replacement for select Nissan Altima and Toyota T100 fitments

Fitment Details

• Fits 1993-1996 Nissan Altima, lower - radiator to thermostat.
• Fits 1997 Nissan Altima, lower.
• Fits 1998-2001 Nissan Altima, lower - radiator to thermostat.
• Fits 1996-1998 Toyota T100, upper.

Detailed Description

Dayco 71668 is a formed radiator coolant hose for cooling system service on select Nissan Altima and Toyota T100 models. Its curved shape supports the original hose routing, helping maintain a clean path between the radiator and thermostat where a straight hose would not match the factory layout. The EPDM material is commonly used in coolant applications for its resistance to heat and coolant exposure, and the hose is specified with equal end diameters for the listed vehicles.

This part cross-references Gates 20795 and Toyota 16571-62050 for the same application. For buyers searching by vehicle, this hose is a direct-fit option for Nissan Altima lower radiator hose replacement and Toyota T100 upper radiator hose service. The Dayco 71668 part number is also useful when matching an OE-style curved hose by size and routing.

Common Replacement Reasons

• Cracked or split radiator hose
• Coolant seepage at the hose body or ends
• Soft, swollen, or heat-aged hose material
• Incorrect hose shape after prior repair
• Loss of proper coolant circulation through the radiator circuit

Installation Notes and Tips

Verify the hose position before installation, since listed applications include lower - radiator to thermostat, lower, and upper locations. Compare the existing hose routing, end diameters, and formed shape to the replacement part before removal. Inspect hose clamps, thermostat necks, and radiator outlets for corrosion or damage, and replace worn clamps as needed during cooling system service.

Quality Assurance

Dayco manufactures this hose to published SAE cooling system specifications for the listed applications. The EPDM construction and formed profile are intended to match the requirements of the specified Nissan Altima and Toyota T100 fitments.