CSF 3756 Radiator

OE-Style Radiator for Hybrid Cooling

CSF 3756 is an OE-style radiator built with an aluminum core and plastic tanks for hybrid cooling applications. It is engineered for the 2011-2016 Kia Optima Hybrid and 2011-2015 Hyundai Sonata Hybrid as the main radiator, with dimensions and hose connections that match the listed fitment.

Key Features

• Aluminum core with plastic tanks for OE-style construction
• Cross-flow design with a single-row core
• Core size: 25 1/16 in. length, 18 5/16 in. width, 5/8 in. thickness
• Inlet: 1 3/8 in. right side; outlet: 1 3/8 in. left side
• Designed for hybrid main radiator applications
• CSF part number 3756

Detailed Description

CSF 3756 radiator is built to match OE-style cooling system requirements for select Hyundai and Kia hybrid sedans. The aluminum core and plastic tank construction follows a common factory-style layout, while the cross-flow configuration and single-row core support efficient coolant flow through the radiator assembly. This radiator is listed for 2011-2016 Kia Optima Hybrid and 2011-2015 Hyundai Sonata Hybrid main radiator applications, making it a direct-fit option for vehicles needing a replacement radiator with the specified inlet and outlet orientation. CSF 3756 is also cross-referenced to Bosch 13249 and Carlson 13531 for the same application.

Common Reasons to Replace

• Coolant leaks from cracked tanks or aged seams
• Restricted cooling performance from internal blockage or corrosion
• Overheating caused by a damaged or inefficient radiator core
• Physical damage from road debris or front-end impact
• Failed OE radiator on a Kia Optima Hybrid or Hyundai Sonata Hybrid

Installation Notes and Tips

Verify inlet and outlet orientation before installation: inlet is on the right and outlet is on the left. Confirm core dimensions, hose size, and mounting points against the original radiator before removal. This radiator does not include a cap, and the listed CSF cap number is 4503 if a matching cap is needed separately. Flush the cooling system and inspect hoses, clamps, and coolant condition before installing the replacement radiator.

Quality Assurance

CSF states that its factories are ISO/TSO certified and that its radiators are engineered to high-performance standards. The brand also validates cooling performance through wind-tunnel testing and supplies a wide range of radiator applications for major vehicle platforms worldwide.