Denso 221-3507 Radiator

Denso 221-3507 Radiator for Mazda 3

The Denso 221-3507 radiator is an OE-style cooling replacement built for 2004-2006 Mazda 3 applications. It uses core dimensions, inlet and outlet sizing, and materials that align with original equipment standards for dependable engine cooling and fitment.

• Core height: 14.4380 in.
• Core width: 26.4370 in.
• Core thickness: 0.6250 in.
• Inlet diameter: 0.9370 in.
• Outlet diameter: 0.9370 in.
• Transmission oil cooler included: No

OE Cooling Performance

Denso supplies radiators to OE car makers worldwide, and the 221-3507 reflects that experience with a radiator configuration engineered to meet strict manufacturer standards. For Mazda 3 owners needing a direct-fit cooling system component, this radiator is built around the dimensions and function required for stable engine temperature control. This part cross-references Spectra Premium CU2696 for the same application.

Vehicle Fitment

• Fits 2004-2006 Mazda 3, N/A.

Common Problems This Radiator Can Address

• Overheating caused by a leaking or restricted radiator
• Coolant loss from cracked tanks or damaged core passages
• Poor heat transfer from an aging cooling system
• Fitment issues when replacing an OE-style Mazda 3 radiator
• Cooling performance decline from corrosion or internal blockage

Installation Notes and Tips

Verify inlet and outlet hose sizes before installation and confirm the radiator matches your vehicle’s cooling system layout. Inspect hoses, clamps, and coolant condition during replacement, and flush the system if contamination or debris is present. This radiator does not include a transmission oil cooler.

Quality Assurance

Denso radiators are built to OE specifications and undergo durability and function testing before release. The 221-3507 is designed to deliver consistent cooling performance and reliable fitment for Mazda 3 applications.