Parts from the Drain plug category for other GMC models:
GMC Acadia I oil drain plug
GMC YUKON (GMT900) oil drain plug
GMC YUKON XL 1500 oil drain plug
GMC Terrain I oil drain plug
GMC YUKON XL 1500 oil drain plug
GMC Envoy II SUV oil drain plug
GMC Yukon I (GMT400) oil drain plug
GMC Yukon XL 2500 oil drain plug
GMC SAVANA 1500 Standard Cargo Van oil drain plug
GMC Sierra Pickup oil drain plug
GMC Sierra III 1500 Crew Cab Pickup oil drain plug
GMC G2500 Vandura oil drain plug
GMC Yukon II (GMT800) oil drain plug
GMC SAVANA 1500 Standard Passenger Van oil drain plug
GMC Sierra III 1500 Extended Cab Pickup oil drain plug

Engine: other spare parts for your Sierra II Extended Cab Pickup model : Sierra II Extended Cab Camshaft, Sierra II Extended Cab Con Rod Bearing, Sierra II Extended Cab Crankcase Breather, Sierra II Extended Cab Crankshaft, Sierra II Extended Cab Cylinder Head Bolts, Sierra II Extended Cab Engine Block, Sierra II Extended Cab Engine Mount, Sierra II Extended Cab Engine Oil, Sierra II Extended Cab Exhaust Valve, Sierra II Extended Cab Inlet Valves, Sierra II Extended Cab Intake Manifold, Sierra II Extended Cab Oil Dipstick, Sierra II Extended Cab Oil Pump, Sierra II Extended Cab Oil Sump, Sierra II Extended Cab Piston, Sierra II Extended Cab Piston Rings, Sierra II Extended Cab Rocker Cover, Sierra II Extended Cab Tappet, Sierra II Extended Cab Timing Belt Cover