I had my 11957 Treadlvac power brake unit rebuilt by Ecklers/White Post. With very light pedal pressure everthing if OK. With harder pressure such as making a normal stop at 25 MPH the unit squeals and there is no power assist. I returned the unit to the rebuilder and they say it checks out OK, I reinstalled it and the probem is still there. I suspect it is an internal vacuum leak. Any one ever have this problem?
I am not happy with the service I got from Ecklers.
ChevGene
1934 Master sedan
1939 Master DeLuxe Town Sedan
1950 Styline DeLuxe Power Glide
1957 Nomad 283 PG
1963 Corvair Convertible