Part #: 3870

CSF 3870 Radiator

⚙️ 17 vehicles fit this part
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Select your vehicle to confirm fitment
Verify this part fits before purchasing — free returns if it doesn't
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OE Direct Replacement — Bolt-on fit, no modifications needed
🚗Fitment: Hyundai and Kia, Elantra, Elantra GT, and Forte
🔄Easy Returns — Return within 60 days for a full refund
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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.

BrandCSF
Part Number3870
Core Thickness1 1/4
Core Width11 5/16
Core MaterialAluminum
Tank MaterialPlastic
Core Length25 9/16
Inlet Diameter1 3/8 left
Outlet Diameter1 3/8 right
Down Flow Or Cross Flow TypeCross flow
Radiator Core Row Quantity1
Cap IncludedNo
Box Height (in)6 5/8
Box Length (in)33 5/8
Box Weight (lbs)9
Box Width (in)19 13/16
Hazardous MaterialNo
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 NoteO.e.m. style plastic tank & aluminum core.

This part fits 17 vehicles. Search below:

YearMakeModelBody TypeLitersCylindersPositionNotes
2024KiaForteSedan1.6LL4N/AUpgraded Heavy Duty Core. 19% Thicker 30mm vs OEM 25mm
2023KiaForteSedan1.6LL4N/AUpgraded Heavy Duty Core. 19% Thicker 30mm vs OEM 25mm
2022KiaForteSedan1.6LL4N/AUpgraded Heavy Duty Core. 19% Thicker 30mm vs OEM 25mm
2021KiaForte1.6LL4N/AOE style design ensures optimal fitment and performance.
2020HyundaiElantra1.6LL4N/AOE style design ensures optimal fitment and performance.
2020HyundaiElantra1.4LL4N/AOE style design ensures optimal fitment and performance.
2020HyundaiElantra GT1.6LL4N/AOE style design ensures optimal fitment and performance.
2020KiaForte1.6LL4N/AOE style design ensures optimal fitment and performance.
2019HyundaiElantra1.4LL4N/AOE style design ensures optimal fitment and performance.
2019HyundaiElantra1.6LL4N/AOE style design ensures optimal fitment and performance.
2019HyundaiElantra GT1.6LL4N/AOE style design ensures optimal fitment and performance.
2019KiaForte1.6LL4N/AOE style design ensures optimal fitment and performance.
2018HyundaiElantra1.4LL4N/AOE style design ensures optimal fitment and performance.
2018HyundaiElantra1.6LL4N/AOE style design ensures optimal fitment and performance.
2018HyundaiElantra GT1.6LL4N/AOE style design ensures optimal fitment and performance.
2017HyundaiElantra1.4LL4N/AOE style design ensures optimal fitment and performance.
2017HyundaiElantra1.6LL4N/AOE 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:

1371025310F330025310M6400HY3010214HY3010225

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.