77-87 GM Truck 21 Inch 1.25/1.5 Outlets AT Dual 14 Inch Cold Case Radiators1977 1987 Chevy GMC Truck Aluminum Performance Radiator. This is the radiator that is 21 inches high overall. For 19 inch tall version, see GMT556AK. 1. 25 inch Upper Hose and 1. 5 inch Lower Hose. For other configuration, see GMT556A21K. These COLD CASE radiators are Tig welded 100 percent aluminum and absolutely beautiful. When you need the biggest and best, look no further than the Cold Case Super Duty Line. All Super Duty kits include 2 row