Dave ,

Your REAR brake cylinders have a 1 & 3/8" piston inside the cylinder .

I come up with the Original GM part # 5450071 for the wheel cylinder .


The ' Filling Station ' has reproduction Rear Wheel Cylinders .for your 1951 3600 ..




Attachments
FS -391 _REAR WHEEL CYLINDERS.JPG (217.78 KB, 104 downloads)

Last edited by '54 3600; 10/27/2017 1:45 AM. Reason: change
1954 3600
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