When I rebuilt the entire brake system on my 1957 2 ton I found that shoes are obsolete/no longer available, I think you will have trouble finding new drums but probably find used. I was able to get rebuild kits for the master cylinder and all six wheel cylinders. I am not using the power brake Hydro-Vac at this point due to internal leakage but with manual brakes and loaded with 105 bales of hay I had no brake issues. Rear axle ratio's are going to keep any of this vintage truck either in the slow lane or the slower lane, mine has a single speed rear end with 7.10 :1 ratio - it tops out at 45 MPH against the governor - doe's not care if it's loaded or empty.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
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