1975 GMC C35 Engine: 4.1L L6; Standard Rotation|Standard Duty Thermal Fan Clutch;. 1975 GMC C35 Engine: 5.7L V8; Standard Rotation|Standard Duty Thermal Fan Clutch|w/ Std Duty Fan Clutch;. 1975 GMC C35 Engine: 4.8L L6; Standard Rotation|Standard Duty Thermal Fan Clutch;.
