1981 GMC G3500 Standard Rotation; Optional Non-Thermal Fan Clutch; w/o A/C;. 1982 GMC G3500 Engine: 4.1L L6; Standard Rotation; Optional Non-Thermal Fan Clutch; w/o A/C;. 1982 GMC G3500 Engine: 5.7L V8; Standard Rotation; Optional Non-Thermal Fan Clutch; w/o A/C;.
