Four Seasons 36991 Engine Cooling Fan Clutch

Four Seasons 36991 Fan Clutch Overview

The Four Seasons 36991 engine cooling fan clutch is a standard-duty thermal replacement built with an aluminum body and non-electronic operation. It is engineered for direct-fit service on select Toyota Previa models and meets OEM specifications for the application.

For 1991-1997 Toyota Previa cooling system service, this fan clutch supports proper fan engagement based on temperature demand. The Four Seasons Fan Clutch line focuses on OE-style replacement parts for thermal fan control, and part number 36991 follows that approach with a flange mount, standard rotation, and import-style clutch design.

Key Features

• Thermal, non-electronic fan clutch design
• Aluminum construction with raw aluminum finish
• Standard-duty use type for everyday cooling system service
• Flange mounting style with 4-bolt, 4-hole pattern
• Clutch maximum diameter: 6.65 in. (168.9 mm)
• Fan bolt circle: 5.35 in. (135.9 mm)
• Mount diameter: 4.18 in. (106 mm)
• Meets or exceeds OEM requirements for the listed application
• Performance rated
• New part, not remanufactured

Detailed Description

Four Seasons 36991 is a thermal engine cooling fan clutch designed for controlled fan engagement as engine temperature rises. Its aluminum construction, standard rotation, and import-style A clutch profile make it a direct replacement choice for select Toyota Previa cooling systems. The unit uses a flange mount with M6 x 1.0 hole threading, a 0.95 in. pilot depth, and a 2.34 in. distance from clutch to mounting flange for proper fitment.

This part cross-references MAHLE 4878 and NGK 5584 for the same application. If you are replacing a worn Toyota Previa fan clutch, Four Seasons 36991 provides the correct thermal control profile for 1991-1997 Toyota Previa service.

What It Helps Address

• Fan clutch slip that reduces cooling fan engagement
• Excessive engine temperature during stop-and-go driving
• Cooling fan noise caused by a worn thermal clutch
• Inconsistent fan operation on a Toyota Previa cooling system
• Loss of proper airflow through the radiator and condenser

Installation Notes and Tips

Verify the mounting flange, bolt circle, pilot dimensions, and rotation before installation. This part is a standard rotation, non-electronic thermal fan clutch with mounting hardware not included. Confirm the vehicle application against the existing unit on 1991-1997 Toyota Previa models before service, and inspect the fan blades, water pump area, and surrounding cooling components during replacement.

Quality Assurance

Four Seasons 36991 is a new replacement part that meets or exceeds OEM requirements and is performance rated for the listed application. It is built for direct-fit cooling system service on compatible Toyota Previa vehicles.