
- OEM-Style Fitment: A direct, bolt-on replacement for a seamless installation.
- Superior Durability: Features a robust, all-aluminum design that is built to last longer than the factory unit.
- Rigorous Testing: Each radiator is individually pressure-tested and serial-number certified, guaranteeing it is 100% leak-free.
- Enhanced Performance: Designed to meet or exceed OE specifications, ensuring your truck stays cool under any condition.
- Trusted Quality: Backed by a 1-year CSF warranty for your peace of mind.

Ensure the long-term health of your 2020-2021 GM 6.6L Duramax L5P with the CSF 3938 OEM Style Replacement Auxiliary Radiator. When your stock cooling system begins to fail, a reliable and durable replacement is essential. This radiator is an ideal solution, engineered as a direct-fit, bolt-in replacement that requires no modifications for installation. It works seamlessly with your truck's existing hoses, brackets, and mounting points, making for a quick and hassle-free repair that restores your cooling system to proper operation.
Key Features
OEM-Style Fitment: A direct, bolt-on replacement for a seamless installation.
Superior Durability: Features a robust, all-aluminum design that is built to last longer than the factory unit.
Rigorous Testing: Each radiator is individually pressure-tested and serial-number certified, guaranteeing it is 100% leak-free.
Enhanced Performance: Designed to meet or exceed OE specifications, ensuring your truck stays cool under any condition.
Trusted Quality: Backed by a 1-year CSF warranty for your peace of mind.
CSF is a recognized leader in automotive cooling, [...]
- OEM-Style Fitment: A direct, bolt-on replacement for a seamless installation.
- Superior Durability: Features a robust, all-aluminum design that is built to last longer than the factory unit.
- Rigorous Testing: Each radiator is individually pressure-tested and serial-number certified, guaranteeing it is 100% leak-free.
- Enhanced Performance: Designed to meet or exceed OE specifications, ensuring your truck stays cool under any condition.
- Trusted Quality: Backed by a 1-year CSF warranty for your peace of mind.