Four Seasons 35937 Engine Coolant Temperature Sender

Temperature Switch for Engine Cooling Control

Four Seasons 35937 is an engine coolant temperature sender built for cooling fan control in select GM applications. It uses a black round male connector with a single terminal and an engine-mounted, male 3/8" pipe fitting for direct replacement service.

Compatible With 1982-1992 Chevrolet, Buick, Pontiac, and GMC applications listed below, including Camaro, Celebrity, Firebird, Century, 6000, Citation II, P20, and P3500 models.

Key Features

• Four Seasons Temperature Switch, part number 35937
• Engine coolant temperature sender for cooling fan operation
• Engine mounted design with 3/8" pipe thread (43/64" x 18)
• Black round connector, male terminal, single-terminal layout
• Fan open/closed operation: open
• Temperature on at 237 and off at 209
• Meets or exceeds OEM requirements

Detailed Description

Four Seasons 35937 is a temperature switch used in engine cooling systems to monitor coolant temperature and trigger fan operation at the specified thresholds. The Temperature Switch line from Four Seasons focuses on direct-fit thermal control components for service replacement, and this unit is specified as an engine-mounted cooling fan switch with a male 3/8" pipe thread. It is a practical replacement for vehicles such as the Chevrolet Camaro, Chevrolet Celebrity, Pontiac Firebird, and GMC P3500 where the original coolant temperature sender is used for fan control.

This part cross-references FEL-PRO 35937 for the same application.

What It Helps Address

• Cooling fan not switching on at the correct coolant temperature
• Cooling fan staying on longer than expected after warm-up
• Faulty coolant temperature sender readings at the engine
• Replacement needs for worn or damaged temperature switch connectors
• Service issues on Chevrolet Camaro, Pontiac Firebird, and related GM cooling systems

Installation Notes and Tips

• Verify the connector style, terminal count, and 3/8" pipe thread before installation.
• Confirm the engine-mounted location and thermostat housing or intake manifold placement against the original part.
• Check the vehicle’s cooling fan control strategy and temperature thresholds before replacing the sender.
• Use the listed fitment to match the exact year, make, and model: Fits 1982-1983 Buick Century, Engine Mounted; In Thermostat Housing; Temperature Switch. Fits 1982-1983 Chevrolet Celebrity, Engine Mounted; In Intake Manifold; Temperature Switch. Fits 1982-1983 Pontiac 6000, Engine Mounted; In Intake Manifold; Temperature Switch. Fits 1982-1983 Pontiac Firebird, With Light; Canada Emissions; Low Speed; w/ Heavy Duty Cooling; With Light; w/o 2 Speed Cooling Fan; Temperature Switch. Fits 1985 Chevrolet Citation II, With Light; w/ Bullet Terminal; With Light; Temperature Switch. Fits 1988 Chevrolet P20, With Light; Coolant Temp; With Light; Temperature Switch. Fits 1989-1992 Chevrolet Camaro, With Light; With Light; Temperature Switch. Fits 1991 GMC P3500, With Light; With Light; Temperature Switch.

Quality Assurance

Four Seasons 35937 is specified to meet or exceed OEM requirements for the listed applications. It is built as a direct replacement temperature switch for compatible GM cooling fan systems.