Brake Problems

Let me add one more thing. you may not be bleeding your brakes properly. I have a friend who insists that the best method is for one person to pump, pump, pump on the brake pedal until the pedal feels firm, and then the guy opens the bleeder valve. That method has NEVER worked for me. It does not even make sense to me. In fact, we have bled brake systems together several times. The first time was his 67 Mustang. After trying his method for about an hour, I INSISTED that we use mine. 20 minutes later we had a firm pedal.
I believe in this method:
1. Start with the wheel furthest from the master cyl.
2. Make sure the MC reservoir is full. And check it frequently during the bleeding process. If the reservoir gets low, and you start sucking air, you start over.
3. Open the bleeder valve and say, "Down". Your assistant will press the brake pedal to the floor and leave it there.
4. Close the bleeder valve and say, "Up". Your assistant will release the brake pedal, let it rise to the top and leave it there.
5. Repeat steps 4 and 5 (KEEPING A CLOSE EYE ON BRAKE FLUID LEVEL) until the fluid is clear with no bubbles. Then do the other 3 wheels.
I believe this is the best method. It pushes clear fluid from the MC all the way to the bleeder valve.