CSF 20021 Automatic Transmission Oil Cooler

CSF 20021 Automatic Transmission Oil Cooler

The CSF 20021 is a parallel-flow automatic transmission oil cooler built for Ford Explorer and Mercury Mountaineer applications from the late 1990s through 2001. Its compact core dimensions and tube-style inlet and outlet make it a direct-fit style solution for transmission fluid temperature control in compatible vehicles.

Key Features

• Parallel-flow construction for efficient fluid cooling
• Core size: 1 in. thick, 7 3/4 in. wide, 9 1/2 in. long
• Tube inlet and tube outlet connections
• Compact design for Ford Explorer and Mercury Mountaineer fitments
• Cross-references Carlson 19013 for the same application
• Cross-references Partslink FO4050147 for the same application

Detailed Description

Built as an automatic transmission oil cooler, the CSF 20021 uses a parallel-flow core layout to move transmission fluid through multiple passages for heat dissipation. The 1-inch core thickness and compact footprint support installation in vehicles where space is limited, while the tube inlet and outlet configuration matches the listed OE-style application. This part number 20021 is listed for 1996-2001 Ford Explorer and 1998-2001 Mercury Mountaineer models, making it a focused replacement choice for those platforms.

For buyers searching for a Ford Explorer transmission cooler or a Mercury Mountaineer automatic transmission oil cooler, CSF 20021 provides a fitment-specific option with dimensions and connection style that align with the application data. The part number 20021 is also useful when cross-referencing OE and aftermarket listings during radiator and cooler replacement work.

What It Helps Address

• Transmission fluid overheating
• Heat buildup during stop-and-go driving
• Reduced cooling performance from a worn or leaking cooler
• Replacement needs after cooler damage or corrosion
• Fitment matching for Ford Explorer and Mercury Mountaineer cooling service

Installation Notes and Tips

Verify the tube inlet and outlet layout against the original cooler before installation. Confirm core dimensions, mounting space, and line routing on the vehicle to ensure the replacement matches the existing cooling system. For 1996-2001 Ford Explorer and 1998-2001 Mercury Mountaineer applications, compare the original part number and connection style before final assembly.

Quality Assurance

CSF is an established cooling-system brand, and this cooler is listed with OE-style interchange references for application matching. This part cross-references Carlson 19013 and Partslink FO4050147 for the same application.