I agree. It makes sense the wayHE phrased it though.

 

drive normal, hit the brakes normal (not like emergency stop). If your steering stays straight while you're doing that, then most certainly the proportioning valve.

 

We still don't know if he has drums all the way around, or if it's a disc/drum system. A 4 wheel drum system won't have a proportioning valve and doesn't reallyneed one. You do the adjustments at the wheel with the star adjusters. Even with the disc-drum setup you can get some adjustment out of the rears this way. I suspect this may be all he needs to do; back off the star adjusters a little and it might fix the problem.

 

He has disc front, and drum rears.

 

OK Hawk, here we go. With disc in front and drums in the rear, you need an ajustable pressure relief type valve in the rear line, I.E. a proportioning valve. Normally front discs need more pressure to operate than drums. If you had drums all around and then replaced the fronts with discs later in life and didnt install a proportioing valve (or a combo valve) then the rears would tend to lock up and you would loose control of the vehicle. This is because drum brakes dont require as much pressure to operate them discs. A combo valve is simply a distribution block with a proportioning valve built in. It really sounds like you dont have a proportiongi valve in your rear line. Under normal circumstances this isnt a big deal, but with a panic stop, its a REAL big deal. A combo valve or proportioning valve will be located near your master cylinder...it will have about 5 or 6 lines runing in and out of it, maybe even have a small electrical connection. A proportioning valve will be down stream of your master cylinder and have only 2 line connections....in and out, with a small nurled **** for making adjustments. The best way to adjust both thypes of valves is to adjust it fuly counter clockwise and go out and drive the car. Slam on the brakes and see which set locks up first. front or rear. If its the fronts, then adjust the knurled **** in one turn and try itagain. Keep doing this until the rears lock up first and then back off 1 turn so that the fronts lock first. After that your all set. Hope this long winded explanation helps and sorry for making if over long guys.

 

Did something I say confuse someone? I didn't mention any brakes locking up.

But if the rears did lock up, it would mean that they have virtually no stopping power compared to the front, so the rear would want to maintain its velocity. I never mentioned the fronts locking up.