CSF 3937 Radiator
OE Quality 60-Day Returns
CSF

CSF 3937 Radiator

Brand CSF 3937
Core Thickness 1 5/8
Core Width 20 5/16
Core Material Aluminum
Tank Material Plastic
Core Length 39 3/8
Inlet Diameter 1 15/16 left
Outlet Diameter 1 15/16 right
Down Flow Or Cross Flow Type Cross flow
Radiator Core Row Quantity 2
Cap Included No
Box Height (in) 8 1/4
Box Length (in) 47 3/8
Box Weight (lbs) 24
Box Width (in) 24 1/8
Hazardous Material No
Inlet Length (in) 20 7/8
Inlet Width (in) 2 3/16
Oil Cooler (in) No
Outlet Length (in) 20 7/8
Outlet Width (in) 2 3/16
Tech Note O.e.m. style plastic tank & aluminum core.
Fits Ram · 11 vehicles

OE-style design. Plastic tank and aluminum core construction matches the original layout.

Cross-flow radiator. Engineered for efficient cooling performance and airflow validation.

ISO/TSO certified. Built in certified factories with over 50 years of radiator production.

Cross-references BBB Industries 13871, Mopar 68322491AA and 68322492AA for the same application. See all 4.

$225.87Free shipping
In stock · usually ships same day before 1pm CST
Step 1 — Confirm fitment
Free return shipping if it doesn't fit when you check fitment here first.
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Step 2 — Quantity
Order total $225.87
Free shipping to the continental U.S.
Free returns within 60 days if it doesn't fit when fitment is verified.
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CSF 3937 Radiator for Ram 2500 and 3500

The CSF 3937 radiator is an OE-style replacement built with an aluminum core and plastic tanks for Ram heavy-duty cooling system service. It is engineered for direct fitment on select 2019-2025 Ram 2500 and Ram 3500 applications, including upgraded heavy-duty coverage for later models.

Key Features

  • CSF radiator, part number 3937
  • OE-style plastic tank and aluminum core construction
  • Cross-flow design with 2-row core layout
  • Core thickness: 1 5/8 in.
  • Core dimensions: 39 3/8 in. length, 20 5/16 in. width
  • Inlet and outlet diameter: 1 15/16 in.
  • Cap not included
  • Built from CSF radiator manufacturing standards used across a wide range of vehicle applications

Detailed Description

CSF 3937 is a replacement radiator designed for Ram 2500 and Ram 3500 trucks that need a direct-fit cooling system component with OE-style packaging. The aluminum core and plastic tank construction follows the original equipment layout, while the cross-flow, 2-row design supports efficient coolant transfer through the radiator assembly. This part number 3937 is listed for 2019-2021 Ram 2500 and Ram 3500 models, plus 2022-2025 Ram 3500 and 2025 Ram 2500 applications with upgraded heavy-duty 16% stronger core coverage.

This radiator cross-references BBB Industries 13871 and Mopar 68322491AA for the same application. For buyers searching Ram 2500 radiator replacement, Ram 3500 radiator replacement, or CSF 3937, this unit matches the OE-style configuration and dimensions needed for proper installation and cooling performance.

What This Radiator Helps Address

  • Coolant temperature rise from a worn or restricted radiator
  • Leaks caused by aging plastic tanks or core fatigue
  • Reduced cooling efficiency under towing or heavy-duty use
  • Fitment issues from non-OE-style replacement parts
  • Cooling system service needs on Ram 2500 and Ram 3500 trucks

Installation Notes and Tips

Verify radiator dimensions, inlet and outlet orientation, and vehicle application before installation. This CSF 3937 radiator uses a cross-flow layout with left inlet and right outlet placement, so matching the original configuration is important for proper fitment. Inspect hoses, clamps, and surrounding cooling system components during replacement to help ensure a complete repair.

Quality Assurance

CSF manufactures radiators to high-performance standards and validates cooling performance through laboratory wind tunnel testing. The brand also produces a broad range of radiator applications for major vehicle platforms, including Ram 2500 and Ram 3500 coverage.

  • Fits 2019-2021 Ram 2500, N/A
  • Fits 2019-2021 Ram 3500, N/A
  • Fits 2022-2025 Ram 3500, N/A
  • Fits 2025 Ram 2500, N/A

Related reading

This part fits 11 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersFuel TypePositionNotes
2025Ram25006.7LL6DIESELN/AUpgraded Heavy Duty 16% Stronger Core
2025Ram35006.7LL6DIESELN/AUpgraded Heavy Duty 16% Stronger Core
2024Ram35006.7LL6DIESELN/AUpgraded Heavy Duty 16% Stronger Core
2023Ram35006.7LL6DIESELN/AUpgraded Heavy Duty 16% Stronger Core
2022Ram35006.7LL6DIESELN/AUpgraded Heavy Duty 16% Stronger Core
2021Ram25006.7LL6DIESELN/AOE style design ensures optimal fitment and performance.
2021Ram35006.7LL6DIESELN/AOE style design ensures optimal fitment and performance.
2020Ram25006.7LL6DIESELN/AOE style design ensures optimal fitment and performance.
2020Ram35006.7LL6DIESELN/AOE style design ensures optimal fitment and performance.
2019Ram25006.7LL6DIESELN/AOE style design ensures optimal fitment and performance.
2019Ram35006.7LL6DIESELN/AOE style design ensures optimal fitment and performance.
Directly replaces or cross-references 4 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
BBB Industries — 13871Mopar — 68322491AA68322492AACH3010390