welcome to the site! The master cyl diameter on my 58 Viking 60 was 1 1/4. Napa had the kit. You will want to rebuild all of the wheel cylinders as well and replace all the brake lines, both rubber and steel. They may look OK on the outside but rot and rust from the inside. Napa shows both the 1 1/4 and 1 1/2 kit for a 59. The 1 1/2" cylinder kit as a UP209. Raybestos part # is MK209 and is 10$ cheaper at Rock Auto than Napa.

Both places should have wheel cylinder kits. There are 2 different styles for the rear so, you need to pull them apart to see which ones you have.


Mike
1955 Chevy 6400 ex-flatbed (no bed now!) sold September 2023
In the Stovebolt Gallery
1958 Chevy 6400 flatbed W/dump
In the Stovebolt Gallery
1959 Chevy Suburban Owned for almost 20 years, Daily Driver -- sold May 2016
In the Stovebolt Gallery

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