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What ever happened to the days when one purchased a quality made in USA after market part, installed it and drove off into the sunset with no further problems? My recent experience with upgrading my power brake booster/proportioning valve/master cylinder assembly demonstrates those days are long gone.
Last summer I upgraded (57 Chevy) my perfectly functioning 7" dual diaphragm booster/master cylinder/proportioning valve with CPP's latest and greatest all chrome 9" dual diaphragm booster/master cylinder/proportioning valve set up for 4WPDB upgrade...spent alot of $$$. My original 7" setup was understandably marginal in performance due to its size, but it worked OK with front disc/rear drum brakes. I upgraded to rear disk brakes and the larger 9" booster/master/prop valve package for better performance.
Initial installation went well. After installation and proper brake bleeding I could not stop brake fluid leaks from included brake fluid lines from the master cylinder to proportioning valve. I called CPP and they sent me a new line kit no charge. Of course, after installation I had to fully bleed the brakes again...not fun. The new line kit stopped the leaking and all was well for a few months. By the way, the upgrade to a full 9" dual diaphragm booster made a huge improvement in braking.
Then I started experiencing occasional front brake dragging, especially after hard stops. I worked with CPP customer support and together we ruled out front caliper malfunction, master cylinder itself, master to booster preload problem or brake rod to pedal adjustment.
After much discussion we decided it was a faulty proportioning valve causing occasional front brake drag. CPP sent me a new proportioning valve no charge. Earlier this week I installed the new proportioning valve and bled the brakes once again...not fun. So far so good...no more front brake dragging. Also, I noticed the replaced proportioning valve was leaking a little at the front rubber boot. The new proportioning valve had been redesigned and no longer has a fitting or boot on the front.
Anyway, CPP has been good with their customer support through this and they honored their guarantee with parts replacements at no charge each step of the way. I'm glad I can do the work myself, but what an uneeded hassle. What if I had to take my car to a shop each time for parts replacement including brake bleeding? If that were the case my conversations with CPP would have taken on a whole new tone.
Hopefully, now I can ride off into the sunset with no further CPP parts problems.
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I know I'm a little late for your party, but as far as brake bleeding goes, an compressed air powered vacuum bleeder from OTC tools (marketed under many other brands) makes bleeding a completely dry brake system a 20 minute process working by yourself.
Thanks for the information. We apologize for the issues you have encountered.
If you need anything please feel free to call me direct as well.
So far, Aaron, the new proportioning valve totally corrected my occasional front brake drag issue. I'm amazed at the difference between the proportioning valve that came with my packaged CPP booster/master/prop valve assembly purchased last year and the replacement prop valve CPP sent me earlier this year. Both prop valves are chrome, but the replacement is much heavier than the original. I suspect the original was aluminum and the replacement is brass, the way it should be. Also, the replacement no longer has a rubber boot in the front like the leaking original.
I hope I did get the correct proportioning valve for 4WDB.