Part Type: Engine Cooling Fan Clutch. Notes: Reverse Rotation; Standard Duty Thermal Fan Clutch; w/ 40 mm. Hex Nut; 33 mm. Reverse Rotation Thermal Standard Duty Fan Clutch. 1993 Ford F-350 Engine: 4.9L L6; Reverse Rotation; Standard Duty Thermal Fan Clutch; w/ 40 mm.