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CSF 3724 Radiator
BMW Radiator Replacement for OE-Style Cooling
CSF Radiator 3724 is an OE-style replacement radiator built with an aluminum core and plastic tanks for BMW cooling system service. It is engineered for cross-flow operation with quick-connect inlet and outlet pipe connections, making it a direct-fit solution for select BMW i3, 320i, 328i, 428i, 435i, 335i, 228i, and M235i applications.
With a 1 1/4-inch core thickness, 23 5/8-inch core length, and 13 5/8-inch core width, this radiator is sized for the listed BMW fitments and uses a single-row core design. CSF also validates radiator performance through lab testing, including wind tunnel evaluation, to support cooling efficiency.
Key Features
- Part number 3724 radiator for select BMW cooling system repairs
- Aluminum core with plastic tanks in an OE-style construction
- Cross-flow design with 1 1/2-inch inlet on the left and 1 1/2-inch outlet on the right
- Single-row core design with 1 1/4-inch core thickness
- Quick-connect inlet and outlet pipe design
- No radiator cap included
- Interchanges with Carlson 13395
Detailed Description
CSF 3724 is a replacement radiator designed for BMW models that use the listed OE-style cooling layout. The radiator features an aluminum core for heat transfer and plastic tanks for a factory-style fit, along with a cross-flow configuration that matches the specified inlet and outlet placement. Core dimensions measure 23 5/8 inches long and 13 5/8 inches wide, with a 1 1/4-inch thickness and one core row.
This radiator is a fit for 2012-2016 BMW 320i, 2012-2016 BMW 328i, 2014-2016 BMW 428i, 2014-2016 BMW 435i, 2012-2015 BMW 335i, and related applications listed below. It also covers BMW i3 Range Extender models from 2014-2021 and BMW i3s Range Extender models from 2018-2019. Part number 3724 is a practical choice when replacing a leaking, damaged, or inefficient radiator in these BMW platforms.
Vehicle Fitment
- Fits 2014-2021 BMW i3, N/A, Range Extender Models Only
- Fits 2018-2019 BMW i3s, N/A, Range Extender Models Only
- Fits 2017-2018 BMW 320i, N/A
- Fits 2014-2016 BMW 228i, N/A, w/o SULEV
- Fits 2015-2016 BMW 228i xDrive, N/A, w/o SULEV
- Fits 2012-2016 BMW 320i, N/A, w/o SULEV
- Fits 2012-2016 BMW 328i, N/A, w/o SULEV
- Fits 2014-2016 BMW 428i, N/A, w/o SULEV
- Fits 2015-2016 BMW 428i Gran Coupe, N/A, w/o SULEV
- Fits 2014-2016 BMW 435i, N/A
- Fits 2014-2016 BMW 435i xDrive, N/A
- Fits 2016 BMW M235i, N/A, w/o SULEV
- Fits 2015-2016 BMW 328i xDrive, N/A, w/o SULEV
- Fits 2013 BMW 328i xDrive, N/A, w/o SULEV
- Fits 2012-2015 BMW 335i, N/A, w/o M Sport Line
- Fits 2012-2015 BMW 335i xDrive, N/A, w/o M Sport Line
- Fits 2012-2013 BMW 325i, N/A, w/o M Sport Line
- Fits 2012-2013 BMW 325i, N/A, w/o SULEV
- Fits 2012-2013 BMW 328i, N/A, w/o M Sport Line
Common Problems This Radiator Can Address
- Coolant leaks from a cracked or aging radiator tank
- Overheating caused by reduced heat dissipation
- Damaged inlet or outlet connections
- Corrosion or internal blockage in the cooling core
- Cooling system service on BMW i3, 320i, 328i, 428i, 435i, 335i, 228i, or M235i models
Installation Notes and Tips
Verify the vehicle’s exact engine and emissions configuration before ordering, especially for w/o SULEV and Range Extender applications. This radiator uses quick-connect inlet and outlet pipe connections and is built for the listed cross-flow layout with inlet on the left and outlet on the right. Confirm hose routing, mounting points, and core dimensions against the original unit before installation.
Quality Assurance
CSF manufactures radiators to high-performance standards and uses lab-based cooling validation, including wind tunnel testing, to evaluate performance. The brand has supplied radiators worldwide for decades and produces a broad range of OE-style cooling components for leading vehicle applications.
This part cross-references Carlson 13395 for the same application.
| Brand | CSF |
| Part Number | 3724 |
| Core Thickness | 1 1/4 |
| Core Width | 13 5/8 |
| Core Material | Aluminum |
| Tank Material | Plastic |
| Core Length | 23 5/8 |
| Inlet Diameter | 1 1/2 left |
| Outlet Diameter | 1 1/2 right |
| Down Flow Or Cross Flow Type | Cross flow |
| Radiator Core Row Quantity | 1 |
| Cap Included | No |
| Box Height (in) | 5 11/16 |
| Box Length (in) | 29 7/16 |
| Box Weight (lbs) | 8 |
| Box Width (in) | 16 7/16 |
| Hazardous Material | No |
| Inlet Length (in) | 13 3/8 |
| Inlet Width (in) | 1 11/16 |
| Outlet Length (in) | 13 3/8 |
| Outlet Width (in) | 1 11/16 |
| Tech Note | O.e.m. style plastic tanks & aluminum core;with quick-connect inl |
This part fits 55 vehicles. Search below:
| Year | Make | Model | Transmission | Liters | Cylinders | Position | Notes |
|---|---|---|---|---|---|---|---|
| 2021 | BMW | i3 | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2020 | BMW | i3 | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2019 | BMW | i3 | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2019 | BMW | i3s | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2018 | BMW | 320i | Manual | 2.0L | L4 | N/A | |
| 2018 | BMW | i3 | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2018 | BMW | i3s | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2017 | BMW | 320i | Manual | 2.0L | L4 | N/A | |
| 2017 | BMW | i3 | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2016 | BMW | 228i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2016 | BMW | 228i xDrive | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2016 | BMW | 320i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2016 | BMW | 328i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2016 | BMW | 428i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2016 | BMW | 428i Gran Coupe | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2016 | BMW | 435i | Manual | 3.0L | L6 | N/A | |
| 2016 | BMW | 435i xDrive | Manual | 3.0L | L6 | N/A | |
| 2016 | BMW | i3 | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2016 | BMW | M235i | Manual | 3.0L | L6 | N/A | w/o SULEV |
| 2015 | BMW | 228i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2015 | BMW | 228i xDrive | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2015 | BMW | 320i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2015 | BMW | 328i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2015 | BMW | 328i xDrive | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2015 | BMW | 335i | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2015 | BMW | 335i xDrive | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2015 | BMW | 428i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2015 | BMW | 428i Gran Coupe | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2015 | BMW | 435i | Manual | 3.0L | L6 | N/A | |
| 2015 | BMW | 435i xDrive | Manual | 3.0L | L6 | N/A | |
| 2015 | BMW | i3 | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2014 | BMW | 228i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2014 | BMW | 320i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2014 | BMW | 328i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2014 | BMW | 335i | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2014 | BMW | 335i xDrive | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2014 | BMW | 428i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2014 | BMW | 435i | Manual | 3.0L | L6 | N/A | |
| 2014 | BMW | 435i xDrive | Manual | 3.0L | L6 | N/A | |
| 2014 | BMW | i3 | 0.6L | L2 | N/A | Range Extender Models Only | |
| 2013 | BMW | 320i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2013 | BMW | 325i | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2013 | BMW | 325i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2013 | BMW | 328i | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2013 | BMW | 328i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2013 | BMW | 328i xDrive | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2013 | BMW | 335i | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2013 | BMW | 335i xDrive | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2012 | BMW | 320i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2012 | BMW | 325i | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2012 | BMW | 325i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2012 | BMW | 328i | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2012 | BMW | 328i | Manual | 2.0L | L4 | N/A | w/o SULEV |
| 2012 | BMW | 335i | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
| 2012 | BMW | 335i xDrive | Manual | 3.0L | L6 | N/A | w/o M Sport Line |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.