Fel-Pro 35404 Engine Coolant Thermostat O-Ring

Fel-Pro 35404 Engine Coolant Thermostat O-Ring

Fel-Pro 35404 is a premium engine coolant thermostat O-ring built for sealing performance in cooling system service. It uses application-specific materials to help deliver vehicle-level sealing that professionals rely on for Ford, Mazda, and related applications.

Key Features

• Premium-grade thermostat O-ring for cooling system sealing
• Application-specific material selection for a precise seal
• Engine coolant thermostat O-ring design for service on compatible Ford and Mazda vehicles
• Fel-Pro sealing technology focused on consistent fit and durability
• Part number 35404 for easy identification and cross-reference

Detailed Description

Fel-Pro 35404 is an engine coolant thermostat O-ring used in cooling system sealing applications where a reliable seal is critical. Fel-Pro gaskets are known for vehicle-specific sealing solutions, and this premium O-ring follows that approach with materials selected for the demands of thermostat service. It is a direct-fit sealing component for a wide range of Ford Ranger, Ford Explorer, Ford Aerostar, Ford Bronco II, Ford Escape, Ford Focus, Mazda Tribute, Mazda B4000, and Mazda Navajo applications.

This part cross-references Gates 33779 and MAHLE C31138 for the same application. Search terms such as Ford Ranger thermostat O-ring, Mazda Tribute coolant thermostat seal, and Fel-Pro 35404 engine coolant O-ring are commonly used by buyers looking for the correct sealing component.

What It Is Used For

• Replacing a worn or flattened thermostat O-ring during cooling system repair
• Restoring a proper seal at the engine coolant thermostat housing
• Addressing coolant seepage around the thermostat sealing surface
• Supporting maintenance on Ford and Mazda cooling system service jobs
• Helping correct leaks caused by age, heat cycling, or seal deterioration

Installation Notes and Tips

Clean the sealing surfaces thoroughly before installation and inspect the thermostat housing for corrosion, pitting, or debris. Verify the application by year, make, and model before service. For body fitment, this part is listed for 2001-2004 Ford Escape, 2004 Ford Focus, 2001-2004 Mazda Tribute, 1991-2000 Ford Explorer, 1986-2000 Ford Ranger, 1994-2000 Mazda B4000, 1990-1997 Ford Aerostar, 1991-1994 Mazda Navajo, and 1986-1990 Ford Bronco II.

Quality Assurance

Fel-Pro focuses on 100% vehicle sealing with application-specific materials, giving this thermostat O-ring a professional-grade sealing profile for cooling system service. Part number 35404 is built to meet the needs of the listed Ford and Mazda applications.