CSF 3718 Radiator

OE-Style BMW Radiator for Cooling Performance

The CSF 3718 radiator is an OE-style replacement built with a plastic tank and aluminum core layout for BMW cooling systems. It is engineered for direct-fit service on select BMW 128i, 323i, 325i, 328i, 328i xDrive, 328xi, 330i, 330Ci, 330xi, and Z4 applications.

CSF’s radiator line is manufactured to high performance standards, with design validation that includes wind tunnel testing and broad application coverage across many vehicle platforms. The 3718 follows that OE-style approach with a cross-flow design and quick-connect inlet and outlet pipe connections.

Key Features

• OE-style plastic tank and aluminum core construction
• Cross-flow radiator design
• 1-row core configuration
• Core thickness: 1 1/4 in.
• Core dimensions: 17 5/8 in. wide x 23 5/8 in. long
• 1 1/2 in. left inlet and 1 1/2 in. right outlet
• Quick-connect inlet and outlet pipe design
• Control sleeve included for the cooling circuit
• Sensor on core not supplied; original sensor must be removed and reused
• Cap not included

Detailed Description

CSF part number 3718 is a replacement radiator designed for BMW cooling system service where an OE-style plastic tank and aluminum core are required. The radiator uses a cross-flow layout with a single-row core to match the factory-style packaging and connection points found on select BMW 128i, 323i, 325i, 328i, 328i xDrive, 328xi, 330i, 330Ci, 330xi, and Z4 models. This makes it a practical choice for BMW radiator replacement work when the original unit shows signs of leakage, overheating, or reduced cooling efficiency.

This CSF 3718 radiator cross-references Spectra Premium CU2882 for the same application.

What This Radiator Helps Address

• Coolant leaks from a cracked or aging radiator tank
• Overheating caused by restricted or inefficient heat transfer
• Temperature instability during stop-and-go driving
• Cooling system service needs after radiator failure
• Fitment issues when replacing an OE-style BMW radiator

Installation Notes and Tips

• Fits 2008-2013 BMW 128i, N/A; 2007-2013 BMW 328i, N/A; 2009-2013 BMW 328i xDrive, N/A; 2006-2011 BMW 323i, N/A; 2006-2011 BMW 325i, N/A; 2009-2011 BMW Z4, N/A; 2007-2008 BMW 328xi, N/A; 2006-2007 BMW 330i, N/A; 2006 BMW 325Ci, N/A; 2006 BMW 325xi, N/A; 2006 BMW 330Ci, N/A; 2006 BMW 330xi, N/A.
• Confirm the original sensor is transferred from the existing radiator, since the sensor on the core is not supplied.
• Use the supplied cooling circuit control sleeve during installation.
• Verify inlet and outlet orientation before installation: inlet left, outlet right.
• Check all hose and quick-connect interfaces for proper seating before refilling the cooling system.

Quality Assurance

CSF manufactures radiators in ISO/TSO-certified facilities and has supplied cooling products worldwide for more than 50 years. The brand reports extensive radiator application coverage and uses engineering validation methods to support cooling performance across its product line.