Denso 221-3603 Radiator

Denso 221-3603 Radiator for Subaru Forester

The Denso 221-3603 radiator is built for 2006-2008 Subaru Forester applications and follows OE-style dimensions for proper cooling system fitment. With a 27.0620-inch core width, 14.1870-inch core height, and 0.6250-inch core thickness, it is sized to match the original radiator layout while supporting consistent engine temperature control.

• Compatible with 2006-2008 Subaru Forester
• Core dimensions: 27.0620 in. wide x 14.1870 in. high x 0.6250 in. thick
• 1.5000 in. inlet and 1.5000 in. outlet connections
• Transmission oil cooler included
• OE-focused radiator configuration for fitment accuracy
• Part number: 221-3603

OE-Style Cooling Performance

Denso supplies radiators to original equipment vehicle manufacturers, and this radiator reflects that OE engineering approach in its tank design, fin pitch, core dimensions, and material selection. The result is a radiator intended to maintain proper coolant flow and heat exchange in Subaru Forester models from 2006 through 2008. If you are replacing a leaking, clogged, or damaged radiator, Denso 221-3603 provides the dimensions and connection sizes needed for a direct replacement-style installation.

This part cross-references Spectra Premium CU2674 and CSF 3391 for the same application.

Common Problems This Radiator Can Address

• Coolant leaks from a cracked or corroded radiator core or tank
• Engine overheating caused by restricted coolant flow
• Transmission fluid temperature concerns when the radiator cooler circuit is failing
• Poor fitment from an incorrect aftermarket radiator
• Reduced cooling efficiency from damaged fins or internal blockage

Installation Notes and Tips

Before installation, verify inlet and outlet hose diameter, mounting points, and transmission cooler line routing against the original unit. Flush the cooling system, inspect hoses and clamps, and replace worn seals or damaged lines as needed. After installation, refill with the correct coolant mixture and bleed air from the system according to Subaru service procedures. Fits 2006-2008 Subaru Forester, N/A.

Quality Assurance

Denso radiators are built to meet OE manufacturer standards for configuration, durability, and function. Each radiator is tested for performance and reliability to help ensure consistent cooling under demanding driving conditions.