1964-1967 Corvette Power Brake Shell Front Seal Genuine GM 5464287 or 5452549 - see # 10
CAVEAT EMPTOR: original Delco Moraine Molded rubber made in the USA; not reproduction; not imported. This cup shaped rubber seal mounts in # 8 the front housing & provides a vacuum seal for # 6 the power piston as it moves back & forth as the brakes are applied & released. The above photo illustrates both front & rear side of part. however the unit of sale is one piece. Only one used per PB. 1964 1965 1966 1967
CAUTION: do not follow the advice in this CF thread.
IT IS ALSO DANGEROUS
Click on Bad advice below
If there is no gasket between the PB vacuum booster and the master cylinder the following will occur.
The PB booster will constantly hiss and pull vacuum from around the plastic power piston supporting the rod that pushes into the master cylinder. When vacuum is sucking here - it literally pulls brake fluid past the master cylinder piston seals and right into the PB booster. Decades ago when I services these EXACT Corvette parts I often found a cup of brake fluid pooled in the bottom of the PB booster. That is not good. Either the seal was absent - torn or worn. This is true for every 63-67 Corvette as well as 68-82 Corvette including similar vintage Delco Moraine PB.