Gates 21727 Premium Molded Coolant Hose

The Gates 21727 Molded Coolant Hose is a dedicated replacement component designed to route coolant through an engine cooling system. It addresses common failure points in automotive cooling by using materials engineered to prevent collapse under vacuum and resist electrochemical degradation, which is the leading cause of hose breakdown.

Constructed with an inner EPDM tube and a synthetic fiber knit reinforcement, this hose is built to hold its structure while circulating fluid. The outer EPDM cover adds protection against under-hood heat, ozone exposure, and harsh chemical coolants. It is factory-shaped to ensure tight, properly sealed connections without requiring you to bend or force a straight hose into place.

When planning your repair, note that the product listing does not provide specific vehicle compatibility lists, inner diameter measurements, or overall lengths. You will need to verify that the 21727 part number matches your vehicle specifications, and you must supply your own hose clamps since mounting hardware is not included.

Verdict: The Gates 21727 is a solid choice for vehicle owners and mechanics seeking a pre-shaped, standard-compliant radiator hose built from resilient EPDM rubber. It is recommended for anyone who has verified this exact part number for their cooling system repair.

A great fit if you:

• Need a direct replacement hose matching the 21727 part number.
• Want a pre-shaped EPDM hose that resists internal vacuum collapse.
• Require materials built to handle heat, ozone, and chemical coolant exposure.

Consider something else if you:

• Need a universal flexible hose rather than a fixed pre-molded shape.
• Expect replacement hose clamps or installation hardware in the package.

What materials are used to make this hose?
It features an EPDM rubber inner tube, synthetic fiber knit reinforcement, and an EPDM outer cover resistant to heat, ozone, and chemical coolants.

What industry standards does this coolant hose meet?
It meets the requirements of SAE 20R4 class D2 and DIN 73411 class A (except for tolerances).

Does this hose prevent electrochemical degradation?
Yes, it is specifically engineered to resist electrochemical degradation, which is the leading cause of coolant hose failure.