Denso 221-3709 Radiator

Denso 221-3709 Radiator for Kia Rio and Rio5

The Denso 221-3709 radiator is an OE-style cooling replacement for select 2006-2011 Kia Rio and Kia Rio5 models. Built to match factory specifications for core size, inlet and outlet dimensions, and transmission cooling integration, it supports stable engine temperature control in daily driving and demanding conditions.

Key Features

• Core height: 14.5620 in.
• Core width: 24.9370 in.
• Core thickness: 0.6250 in.
• Inlet diameter: 0.9370 in.
• Outlet diameter: 0.9370 in.
• Transmission oil cooler included
• OE-focused fitment for Kia Rio and Kia Rio5 applications

Detailed Description

Denso part number 221-3709 is engineered as a direct radiator replacement for 2006-2011 Kia Rio and 2006-2011 Kia Rio5 models. Denso supplies radiators to original equipment vehicle manufacturers worldwide, and this unit reflects that OE experience through factory-matched configuration, materials, and dimensional accuracy. The radiator is built to support proper coolant flow and heat transfer, with a core design that aligns with the original application requirements.

This radiator includes a transmission oil cooler and uses 0.9370-inch inlet and outlet connections. For buyers searching for a Kia Rio radiator, Kia Rio5 radiator, or Denso 221-3709 replacement, this part provides the specifications needed for a straightforward OE-style cooling system repair.

This part cross-references Spectra Premium CU2820 and CSF 3293 for the same application.

What It Helps Address

• Engine overheating caused by a failing radiator core
• Coolant leaks from aged or damaged radiator assemblies
• Reduced cooling efficiency from restricted internal passages
• Transmission fluid temperature control concerns in equipped vehicles
• Fitment issues from incorrect aftermarket radiator dimensions

Installation Notes and Tips

Verify core dimensions, inlet and outlet size, and transmission cooler routing before installation. Flush the cooling system, inspect hoses and clamps, and confirm the radiator mounts securely in the factory location. After installation, refill with the correct coolant mixture and bleed air from the system according to the vehicle service procedure.

Quality Assurance

Denso states that its radiators are built to OE standards and undergo durability and function testing before release. That manufacturing approach supports consistent fitment and dependable cooling performance for 2006-2011 Kia Rio and Kia Rio5 applications.