CSF 3100 Radiator
OE Quality 60-Day Returns
CSF
 1 Row Plastic Tank Aluminum Core

CSF 3100 Radiator

Brand CSF 3100
Box Height (in) 4 14/16
Box Length (in) 29 7/8
Box Weight (lbs) 8
Box Width (in) 20 13/16
Cap Included No
Core Length 13 3/8
Core Material Aluminum
Core Thickness 5/8
Core Width 27 1/16
Csf Cap Number 4503
Down Flow Or Cross Flow Type Down Flow
Hazardous Material No
Inlet Diameter 1 1/2 Centre
Inlet Length (in) 27 13/16
Inlet Width (in) 1 5/8
Oil Cooler (in) 14 3/4 (high-effeciency Concentric Type)
Outlet Diameter 1 1/2 Left
Outlet Length (in) 27 13/16
Outlet Width (in) 2
Radiator Core Row Quantity 1
Tank Material Plastic
Tech Note O.E.M. style Plastic tanks & Aluminum core.
Product line 1 Row Plastic Tank Aluminum Core
Fits Subaru · 14 vehicles

OE-style construction. Plastic tanks and an aluminum core mirror the original design.

1-row core. Balanced cooling performance in a compact radiator design.

Wind tunnel tested. Engineered to validate cooling performance in lab conditions.

Cross-references Anchor 2331, APDI 8012331 and Spectra Premium CU2331 for the same application. See all 7.

$106.04Free shipping
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Step 2 — Quantity
Order total $106.04
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Free returns within 60 days if it doesn't fit when fitment is verified.
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OE-Style Radiator for Subaru Cooling Service

This CSF radiator is built as an OE-style replacement with plastic tanks and an aluminum core for Subaru cooling system service. It is designed for 2000-2004 Subaru Legacy and Outback, plus 2003-2006 Subaru Baja applications that use the listed down-flow configuration.

Key Features

  • CSF Part Number 3100
  • 1-row radiator with aluminum core and plastic tanks
  • Down-flow design for the listed Subaru applications
  • Core thickness: 5/8 in.
  • Core width: 27 1/16 in. and core length: 13 3/8 in.
  • Inlet diameter: 1 1/2 center; outlet diameter: 1 1/2 left
  • Integrated oil cooler: 14 3/4 in. high-efficiency concentric type
  • OE-style plastic tank and aluminum core construction

Product Details

CSF 3100 is a direct-fit radiator built around an OE-style plastic tank and aluminum core layout. CSF manufactures radiators to high-performance standards and validates cooling performance in laboratory wind tunnel testing, with production backed by decades of global supply experience. This radiator is listed for Subaru Baja, Subaru Legacy, and Subaru Outback models in the years shown, making it a practical choice when replacing a worn or leaking factory-style radiator.

This part cross-references Spectra Premium CU2331 for the same application.

What This Radiator Helps Address

  • Coolant leaks from aging plastic tanks or seams
  • Restricted cooling performance from a deteriorated radiator core
  • Overheating caused by reduced heat transfer efficiency
  • Transmission or engine cooling concerns tied to radiator wear
  • Replacement needs after corrosion, cracking, or physical damage

Installation Notes and Tips

Verify the inlet and outlet locations, core dimensions, and down-flow layout before installation. This radiator does not include a cap, and the listed application notes specify use of a Mini 16 psi cap where required. Confirm vehicle-specific hose routing and cooler connections on Subaru Legacy, Subaru Outback, and Subaru Baja models before final assembly.

Quality Assurance

CSF states that its factories are ISO/TSO certified and that its radiators are engineered for cooling performance validation. The brand has supplied radiators worldwide for more than 50 years and offers a broad catalog covering many vehicle applications.

Related reading

This part fits 14 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersPositionNotes
2006SubaruBaja2.5LH4N/AOE style design with Mini 16 psi cap.; 1 Row Plastic Tank Aluminum Core
2005SubaruBaja2.5LH4N/AOE style design with Mini 16 psi cap.; 1 Row Plastic Tank Aluminum Core
2004SubaruBaja2.5LH4N/AOE style design with Mini 16 psi cap.; 1 Row Plastic Tank Aluminum Core
2004SubaruLegacy2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
2004SubaruOutback2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
2003SubaruBaja2.5LH4N/AOE style design with Mini 16 psi cap.; 1 Row Plastic Tank Aluminum Core
2003SubaruLegacy2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
2003SubaruOutback2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
2002SubaruLegacy2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
2002SubaruOutback2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
2001SubaruLegacy2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
2001SubaruOutback2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
2000SubaruLegacy2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
2000SubaruOutback2.5LH4N/AOE Style Design; Use Mini, 16 psi Cap; L, LS, LSD; 1 Row Plastic Tank Aluminum Core
Directly replaces or cross-references 7 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
Anchor — 2331APDI — 8012331Spectra Premium — CU233145111 AE00A45111 AE01ASU3010109SU3010110