Chevy Duty , at.....
www.chevyduty.com
has 1964 as the first year for the self adjusting brakes.
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1964
The dash is now full cab width and has a lip along entire top edge that forms a shelf to reduce glare. First year for self-adjusting brakes. Factory in dash air conditioning optional. Emblems are a square with series designation embossed and bowtie on top.
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