CSF 3515 Radiator

CSF 3515 Radiator Overview

CSF 3515 is an OE-style radiator built with a plastic tank and aluminum core for Subaru cooling system service. It is designed for applications such as the Subaru Impreza, WRX, WRX STI, Forester, Outback, Legacy, Crosstrek, and XV Crosstrek across 2005-2017 model years.

The CSF 1 Row Plastic Tank Aluminum Core line focuses on factory-style fitment with performance validation from lab testing and wind tunnel evaluation. CSF has manufactured radiators for decades, supplying a wide range of vehicle applications worldwide.

Key Features

• Part number: 3515
• 1-row radiator with aluminum core and plastic tanks
• Down-flow design
• Core thickness: 5/8 in.
• Core width: 27 in.; core length: 13 3/8 in.
• Inlet diameter: 1 9/16 in. left; outlet diameter: 1 9/16 in. right
• High-efficiency plate-type oil cooler: 14 3/4 in.
• OEM-style layout with dual-size heater pipe on top right-hand side, plug, and dual oil cooler fittings
• Cap not included; CSF cap number 4540

Detailed Description

CSF 3515 is engineered as a direct-fit replacement radiator for Subaru cooling systems that use a plastic tank and aluminum core construction. The radiator’s down-flow layout, OE-style dimensions, and integrated oil cooler provisions make it a practical choice for Subaru Impreza, WRX, WRX STI, Forester, Outback, Legacy, Crosstrek, and XV Crosstrek service work. This part number 3515 is built to match the factory-style configuration found on multiple Subaru platforms from 2005 through 2017.

This part cross-references Spectra Premium CU2777 for the same application.

What It Helps Address

• Coolant leaks from aging plastic tank radiator assemblies
• Restricted heat transfer caused by a worn or clogged core
• Transmission or engine cooling concerns tied to radiator deterioration
• Fitment issues when replacing an OE-style Subaru radiator
• Cooling system service on Subaru Impreza, WRX, Forester, and related models

Installation Notes and Tips

Verify radiator dimensions, inlet and outlet orientation, and oil cooler connections before installation. This radiator uses a down-flow configuration with left-side inlet and right-side outlet, and it does not include a cap. Some listed Subaru applications note use of a mini 16 psi cap and a straight oil cooler fitting pipe, rubber cap, hose clamp, and rubber sleeve; confirm the exact vehicle configuration before installation. Part number 3515 should be matched to the vehicle’s original radiator layout and hose routing.

Fits 2016-2017 Subaru Crosstrek, N/A. Fits 2012-2016 Subaru Impreza, N/A. Fits 2015 Subaru XV Crosstrek, N/A. Fits 2008-2014 Subaru Impreza, N/A. Fits 2012-2014 Subaru WRX, N/A. Fits 2014 Subaru WRX STI, N/A. Fits 2013-2014 Subaru XV Crosstrek, N/A. Fits 2009-2013 Subaru Forester, N/A. Fits 2013 Subaru WRX STI, N/A. Fits 2005-2010 Subaru Outback, N/A. Fits 2005-2009 Subaru Legacy, N/A.

Quality Assurance

CSF states that its factories are ISO/TSO certified and that its radiators are engineered to high-performance standards with cooling validation testing. The brand also notes more than 30 million units sold and over 10,000 radiator models manufactured for leading vehicle applications.