OER Parts offers a wide selection of Brake Components for your 1989 GMC Truck. OER Parts offers 1989 GMC Truck Wheel Cylinders, 1989 GMC Truck Front Wheel Cylinders 1989 GMC Truck Rear Wheel Cylinders, 1989 GMC Truck Wheel Cylinder Retainer, 1989 GMC Truck Drum Brake Bleeder Screws, 1989 GMC Truck Front Wheel Cylinder Repair Set, 1989 GMC Truck Rear Wheel Cylinder Repair Set, and 1989 GMC Truck Wheel Cylinder Pins.