Four Seasons 36999 Engine Cooling Fan Clutch

Four Seasons 36999 Heavy Duty Fan Clutch

The Four Seasons Fan Clutch 36999 is a thermal, heavy-duty engine cooling fan clutch built with an aluminum body and standard rotation. It is a new, non-electronic replacement that meets or exceeds OEM requirements and is performance rated for demanding cooling-system service. This part is a direct-fit option for select Cadillac Commercial Chassis, Fleetwood, DeVille, Eldorado, and Seville applications.

Key Features

• Heavy Duty thermal fan clutch for engine cooling control
• Aluminum construction with raw aluminum finish
• Standard rotation design
• Flange mounting style with 4-bolt, 4-hole pattern
• Clutch maximum diameter: 7.2 in.
• Overall height: 3.95 in.
• Fan bolt circle: 3.25 in. (82.6 mm)
• Mount diameter: 2.43 in. (62 mm)
• Meets or exceeds OEM specifications
• Non-electronic, thermal operation

Product Details

Four Seasons Fan Clutch 36999 is part of the Four Seasons fan clutch line, a cooling-system product range focused on thermal fan clutch replacement for passenger and commercial vehicles. This heavy-duty C-style clutch uses a flange mount, 5/16-18 hole thread, and standard rotation to match the original cooling fan drive setup on supported Cadillac applications. It is a new replacement part with a 7.2-inch clutch diameter, 2.25-inch distance from clutch to mounting flange, and 1.03-inch pilot depth for proper fitment in the cooling assembly.

Fits 1977-1984 Cadillac Commercial Chassis, N/A. Fits 1977-1984 Cadillac Fleetwood, N/A. Fits 1977-1982 Cadillac DeVille, N/A. Fits 1980-1981 Cadillac Eldorado, N/A. Fits 1980-1981 Cadillac Seville, N/A. This part cross-references Gates 22041 and 22042 for the same application.

Common Cooling Issues This Part Addresses

• Fan clutch engagement that no longer responds correctly to engine temperature
• Reduced airflow through the radiator at idle or low road speed
• Cooling fan slip that can affect engine temperature control
• Noisy or inconsistent fan clutch operation
• Replacement needs on aging Cadillac cooling systems

Installation Notes and Tips

Verify the mounting flange, bolt circle, pilot diameter, and overall height against the original part before installation. This thermal fan clutch uses standard rotation and a 4-bolt flange pattern, so alignment with the fan and water-pump drive setup is important for correct operation. Mounting hardware is not included, so reuse or source the required hardware separately if needed.

Quality Assurance

Four Seasons 36999 is a new, performance-rated fan clutch that meets or exceeds OEM specifications. Its heavy-duty aluminum construction and thermal design support consistent cooling-system operation in the listed Cadillac Commercial Chassis, Fleetwood, DeVille, Eldorado, and Seville applications.