2003 Chevrolet C8500 Engine: 8.1L V8; Standard Rotation; Severe Duty Thermal Fan Clutch;. 2009 Chevrolet C8500 Engine: 8.1L V8; Standard Rotation; Severe Duty Thermal Fan Clutch;. 2004 Chevrolet C8500 Engine: 8.1L V8; Standard Rotation; Severe Duty Thermal Fan Clutch;.