I have a 98 F150 4x4. A few years ago my master cylinder went bad so I had it replaced by Ford. Ever since then Ive had soft brakes. Ive dealt with it for years but just decided to figure out why. Ive tested my master cylinder and I know its good. I have vaccuum bled my brakes. My pedal will go 2/3 of the way to the floor before I finally get good stopping power. Also whenever I go around a corner I can hear the brake pads rub against the rotor and start squeeking. Possibly bad hardware on the caliper?

 

Anyone?

 

Spongy brakes usually mean vapor (air) in the lines somewhere and I don't think you can be sure that bleeding the brakes will get rid of it. Brake fluid loses its ability to fight moisture as time passes so it should be changed to keep the brake fluid and any moisture in the brake lines from vaporizing. When you said you bled your brakes did you replace all the brake fluid in the lines?

See the comment about moisture in the line causing spongy brakes below:

http://www.valvoline.com/carcare/art...=ccr20011001bb