Facet 7.8399S Engine Coolant Thermostat

Engine Coolant Thermostat for Toyota and Lexus

Facet 7.8399S is an engine coolant thermostat for a wide range of Toyota, Lexus, Scion, Mitsubishi, Pontiac, Chevrolet, and Ford applications. It is specified with a 180°F opening temperature for many listed vehicles, helping maintain proper coolant flow and operating temperature.

Key Features

• Facet engine coolant thermostat, part number 7.8399S
• 180°F opening temperature on listed applications
• Compatible with many Toyota Camry, Corolla, RAV4, Highlander, Sienna, and Avalon models
• Also listed for Lexus ES350, RX350, RX450h, and related applications
• Fits additional Mitsubishi, Scion, Pontiac, Chevrolet, and Ford vehicles shown in the fitment data

Detailed Description

Use Facet 7.8399S when replacing a worn or temperature-inconsistent thermostat in cooling systems that require a 180°F opening specification. This engine coolant thermostat is listed for numerous Toyota and Lexus platforms, including Toyota Camry, Toyota Corolla, Toyota RAV4, Toyota Highlander, Lexus ES350, and Lexus RX350 applications. The fitment data also includes Scion tC and xB, Mitsubishi Eclipse and Galant, Pontiac Vibe, Chevrolet Prizm, and Ford Taurus coverage.

This part number, 7.8399S, appears across multiple year ranges and engine configurations, including several Toyota and Lexus models where gasket notes vary by application. Review the fitment notes carefully before ordering to confirm the correct thermostat style for your vehicle.

What It Helps Address

• Engine running too cool or too warm
• Delayed warm-up after cold starts
• Temperature fluctuation on the gauge
• Cooling system service on high-mileage vehicles
• Replacement of a sticking or worn thermostat

Installation Notes and Tips

• Verify the exact year, make, model, and fitment note before installation.
• Check whether your application lists a gasket as included or not provided.
• Inspect the thermostat housing and sealing surfaces during service.
• Refill and bleed the cooling system according to the vehicle service procedure.

Quality Assurance

Facet 7.8399S is cataloged as an engine coolant thermostat for the listed applications and opening temperature specification. This part cross-references Standard Motor Products (e.g., 14379, 14380) for the same application.