Gates Molded Coolant Hose 21216 - OE-Style Pre-Formed EPDM Replacement for Radiator & Heater Lines

The Gates 21216 is a ready-to-install molded coolant hose built to replace upper, lower, bypass and heater hose applications with OE-level fit and durable EPDM construction.

If you need a direct-replacement radiator or coolant hose without visiting an original-equipment dealer, this molded Gates hose gives you a pre-formed, reinforced option engineered for modern cooling systems. It’s part of Gates’ broad molded coolant hose lineup, designed to match factory shapes and routing so clamps and flanges seal correctly and installation is faster. Materials and reinforcement are chosen to withstand vacuum, heat, ozone and the chemical action of modern engine coolants.

How does this hose fit my vehicle and save installation time?

The 21216 comes pre-shaped to the contours and routing of the intended OE application so you don’t need to bend or trim it. That saves fitting time and reduces the chance of leaks or pinch points. Its replacement geometry keeps clamps aligned and mating surfaces flush for a reliable seal.

• Pre-formed shape for precise OE-style routing
• Direct-replacement dimensions to match factory joints
• Reduces fitting adjustments and installation rework

What materials and construction make this hose durable?

The hose uses an EPDM inner tube and an EPDM outer cover with synthetic fiber knit reinforcement between them, a combination that resists the common failure modes in coolant systems. The compound and reinforcement limit collapse under vacuum and resist electrochemical degradation that often shortens hose life.

• EPDM tube and cover for heat, ozone and coolant resistance
• Synthetic fiber knit reinforcement for pressure and shape retention
• Materials engineered to resist vacuum collapse and internal degradation

Does this hose meet industry performance standards?

Gates designed the 21216 to meet relevant SAE and DIN criteria for molded coolant hoses, ensuring consistent physical and chemical properties across production. While tolerances can vary, the hose aligns with SAE 20R4 class D2 and DIN 73411 class A requirements, providing confidence for most replacement applications.

• Manufactured to SAE 20R4 class D2 specifications
• Meets DIN 73411 class A requirements (except tolerances)
• Quality control to ensure dimension and material consistency

How does the 21216 resist common failure causes in coolant hoses?

The hose is formulated and reinforced to fight the main mechanisms that lead to premature failures, such as electrochemical breakdown and vacuum-induced collapse. The result is a longer service interval and more reliable performance under varied engine operating conditions.

• Compounds reduce electrochemical degradation from coolant chemistry
• Reinforcement prevents wall collapse during vacuum events
• Outer EPDM resists ozone and heat cracking for extended life

Who is this for: The Gates 21216 molded coolant hose is aimed at DIY mechanics, independent shops and fleet technicians who want a factory-fit replacement without the dealer markup. It suits any repair or maintenance task that requires a pre-shaped, OE-equivalent coolant hose built for modern engine coolant formulations and demanding operating conditions.