Dayco 70870 Radiator Coolant Hose

Dayco 70870 Curved Radiator Hose

Dayco 70870 is a curved radiator coolant hose built for cooling-system service where a 3-inch inside diameter is required at both ends. Made from EPDM rubber in black, this single I.D. hose is specified to SAE J20R4 Class D-1 and SAE J1684 Type EC standards for radiator hose applications.

For buyers searching for a Dayco curved radiator hose, 3 inch radiator coolant hose, or Dayco 70870 replacement hose for truck and heavy-duty cooling systems, this part delivers the dimensions and material details needed for a direct match. It is also a practical cross-reference option for applications listed under ACDelco 20114S or Gates 21042.

Key Features

• Brand: Dayco Curved Radiator Hose
• Part number: 70870
• EPDM construction for coolant-system use
• Black finish
• 3-inch inside diameter at End 1 and End 2
• Single I.D. hose design
• Meets SAE J20R4 Class D-1 and SAE J1684 Type EC specifications
• No heat shield and no protective sleeve

Product Details

Dayco Curved Radiator Hose 70870 is a molded coolant hose designed for radiator and engine-cooling routing where a curved shape is needed. The EPDM rubber construction is suited to coolant exposure and temperature cycling, while the 12-inch trunk height helps identify the hose profile for replacement matching. This hose is a strong search match for Dayco 70870, curved radiator hose 3 inch, and radiator coolant hose replacement for truck cooling systems.

When comparing fitment by dimensions, verify the hose routing, bend shape, and end diameters against the original part before installation. This part cross-references ACDelco 20114S and Gates 21042 for the same application.

Common Cooling Issues It Can Address

• Cracked or split radiator hose material
• Coolant leaks at hose connections
• Softening or swelling from heat and age
• Restricted coolant flow from a deteriorated hose
• Incorrect hose shape or diameter during replacement

Installation Notes

Inspect the radiator neck, water outlet, and clamps before installing Dayco 70870. Confirm the 3-inch inside diameter on both ends, the curved profile, and the 12-inch trunk height against the removed hose to ensure proper routing. Use clean mating surfaces and verify clamp placement after the cooling system is refilled and bled.

Quality Assurance

Dayco manufactures cooling-system hoses to published SAE specifications, including SAE J20R4 Class D-1 and SAE J1684 Type EC for this part. That specification-based construction supports consistent material and dimensional identification for replacement work.