Dorman M98953 Master Brake Cylinder for 74-83 P30 P35/P3500 G30 G35/G3500 Van

1983 GMC P3500 Rear Drum Brakes Bore: 1.3125 In.; Stamped 1605. 1982 GMC P3500 Rear Drum Brakes Bore: 1.3125 In.; Stamped 1605. 1981 GMC P3500 Rear Drum Brakes 9,000 to 10,000 Lb. 1980 GMC P3500 Rear Drum Brakes 9,000 to 10,000 Lb.