Proportion valve / brake system

[tard01]

So trying to get my hands on the proportion valve for the brake system. trying to work out a pressure problem im bhavbing. i have already replaced teh master cylinder calipers brake pads and the rotors and teh rear drums and shoes and a wheel cylinder.


oreilly's telling me they dont carry these cause they are dealer parts, but the dealer is telling me they're no longer produced and hence are not carried in stock.

while doing work on the truck, the constanbt troubleshooting has worn out the nuts/bolts on the brake lines and i've been debating rebuilding the brake line system frmo scratch. they're all the original parts - 1975 c10.

anyone know or can recommend where i can get a new proportion valve -- or, are they entire necessary? can i find an alternate means of splitting them?




for background on issue,
originally felt like major air in lines.
bled brakes, improved, but still lacking stopping significantly.
replaced rotor/pads/caliper/master cylinder/drum/shoes/wheel cylinder(1)
not much improvement.
still had to pump, and still had to exert a large amount of force to get any pressure. it never felt like the front brakes were ever biting. felt like almost all my stopping power was from rear.

so i was working on replacing the 2 wheel cylinders in the rear cause i noticed they were bleeding spo i decided to replace abnd in the process, i striipped the bolt on the brake line. i was going to cut it off and re-place it, but the splitter for the brake line that goes onto the axle was also so rusted it was stripping.

so my options... i can either cut the rear line and replace that rear segment... but that doesnt solve my front end biting problem... or i can replace the proportion valve in the front.

my concern is that its clogged up and that is whyt i am having to exert so much pressure on the brake just to be abloe to get any form of bite from the front. when i initially bled the system the first timew, there was a lot of small metal chunks as well.


the entire front braking system has been replaced minus the lines themselves and the proportion valve.