Another picture with more of the pieces you'll see once you get the drum off. This taken from the 1939-53 GMC Master Parts Book. The GMC 150 model has the same brakes as your 3600. The red V points to the adjuster wheels.
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Last edited by Bill Hanlon; 11/22/2024 3:46 PM.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.