Proportioning Valve availability??

[Huck]

My brakes suck and the best guess is the proportioning valve is shot. I tried resetting it with the little pin at the end but ----it doesn't appear to exist. I know I can buy one of these valves from parts dealers for around $90. which is way too high for what it is. Anyone have a source for new or rebuilt valves at a reasonable price? I don't want a used one as I've tried that route.
It's for a 72 truck/blazer. Any help will be greatly appreciated---Huck

[canarykid]

Are you sure it is your proportioning valve??? I went through a brake problem and thought it was that too. Do all the brakes have fluid going to them? Did you try opening the bleeder on the valve to see if fluid comes out? Let me know what it is doing and maybe I can help.

[9footfan]

try many of the rebuilders in hemmings magazine if you prove it to the prop valve and do not want to shell out $90 for a new one. just fyi.

[Huck]

I have found a used proportioning valve that has the front pin thingy. The master cylinder was supposely a rebuilt. I've replaced the rear wheel cylinders, the shoes are fine as are the drums. I checked the front calipers, had the roters resurfaced. ---and now, same problem as before. When you apply the brakes, the pedal goes half way to the floor and the Blazer tires squeel---can't tell if the front or back are grabbing. The freakin brake light is one despite my pushing--pullng the front thingy on the prop valve. The books don't give a decent process to follow so that you can identify what is wrong where. I've bleed both the front and the rear---yet same !@#$%^.
Any ideas of where and how to begin to get this SOB stopping better then a 61 falcon!???

[botboy]

Does your truck have disks or drums in the front? I have a prop valve from a '67 with 4 wheel drums, will sell for $40 shipped.