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CSF 3870 Radiator
Overview of CSF Radiator Part 3870 for Hyundai and Kia
The CSF radiator part number 3870 is designed specifically for select Hyundai and Kia models, including the Elantra, Elantra GT, and Forte. This radiator features a durable aluminum core combined with plastic tanks, engineered to provide reliable cooling performance for your vehicle.
- Core thickness: 1 1/4 inches
- Core width: 11 5/16 inches
- Core length: 25 9/16 inches
- Aluminum core material with plastic tanks
- Cross flow design for efficient heat dissipation
- Inlet and outlet diameter: 1 3/8 inches (left inlet, right outlet)
- Single-row radiator core
- Cap not included
Detailed Radiator Specifications and Features
This CSF radiator (part number 3870) utilizes a cross flow design, which allows coolant to flow horizontally through the aluminum core, improving heat transfer efficiency. The core measures 1 1/4 inches thick, 11 5/16 inches wide, and 25 9/16 inches long, providing ample surface area for effective cooling. The plastic tanks are designed to match original equipment manufacturer (OEM) specifications, ensuring compatibility and durability. Both the inlet and outlet have a diameter of 1 3/8 inches, positioned on the left and right sides respectively, facilitating straightforward hose connections.
Compatible Vehicles and Common Applications
- Hyundai Elantra radiator replacement
- Hyundai Elantra GT cooling system repair
- Kia Forte radiator upgrade or replacement
- Addressing overheating issues in Hyundai and Kia models
- Replacing damaged or leaking radiators in compatible vehicles
Installation Notes and Tips
When installing the CSF radiator part 3870, ensure all coolant hoses match the 1 3/8 inch inlet and outlet diameters for proper fitment. Since the radiator does not include a cap, reuse the existing cap or source a compatible replacement. Verify the radiator core orientation matches the cross flow design for optimal performance. It is recommended to flush the cooling system before installation to prevent contamination and ensure efficient operation.
Quality Assurance and Warranty Information
CSF radiators are manufactured to meet OEM standards, featuring an aluminum core and plastic tanks designed for durability and heat resistance. While specific warranty details are not provided here, CSF products typically come with manufacturer-backed warranties to cover defects in materials and workmanship. Always consult the product documentation or manufacturer for exact warranty terms.
| Brand | CSF |
| Part Number | 3870 |
| Core Thickness | 1 1/4 |
| Core Width | 11 5/16 |
| Core Material | Aluminum |
| Tank Material | Plastic |
| Core Length | 25 9/16 |
| Inlet Diameter | 1 3/8 left |
| Outlet Diameter | 1 3/8 right |
| Down Flow Or Cross Flow Type | Cross flow |
| Radiator Core Row Quantity | 1 |
| Cap Included | No |
| Box Height (in) | 6 5/8 |
| Box Length (in) | 33 5/8 |
| Box Weight (lbs) | 9 |
| Box Width (in) | 19 13/16 |
| Hazardous Material | No |
| Inlet Length (in) | 11 15/16 |
| Inlet Width (in) | 1 9/16 |
| Oil Cooler (in) | No |
| Outlet Length (in) | 11 15/16 |
| Outlet Width (in) | 1 9/16 |
| Tech Note | O.e.m. style plastic tank & aluminum core. |
This part fits 17 vehicles. Search below:
| Year | Make | Model | Body Type | Liters | Cylinders | Position | Notes |
|---|---|---|---|---|---|---|---|
| 2024 | Kia | Forte | Sedan | 1.6L | L4 | N/A | Upgraded Heavy Duty Core. 19% Thicker 30mm vs OEM 25mm |
| 2023 | Kia | Forte | Sedan | 1.6L | L4 | N/A | Upgraded Heavy Duty Core. 19% Thicker 30mm vs OEM 25mm |
| 2022 | Kia | Forte | Sedan | 1.6L | L4 | N/A | Upgraded Heavy Duty Core. 19% Thicker 30mm vs OEM 25mm |
| 2021 | Kia | Forte | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2020 | Hyundai | Elantra | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2020 | Hyundai | Elantra | 1.4L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2020 | Hyundai | Elantra GT | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2020 | Kia | Forte | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2019 | Hyundai | Elantra | 1.4L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2019 | Hyundai | Elantra | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2019 | Hyundai | Elantra GT | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2019 | Kia | Forte | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2018 | Hyundai | Elantra | 1.4L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2018 | Hyundai | Elantra | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2018 | Hyundai | Elantra GT | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2017 | Hyundai | Elantra | 1.4L | L4 | N/A | OE style design ensures optimal fitment and performance. | |
| 2017 | Hyundai | Elantra | 1.6L | L4 | N/A | OE style design ensures optimal fitment and performance. |
* 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.