I have some brake problems on my '94 Sport that I haven't been able to track down. It started when I noticed that my brake lights weren't coming on unless I pushed the pedal in practically to the floor.

My first thought was that the brake light switch on the pedal was bad. I replaced it, but the problem was still there. In the course of driving around listening carefully to hear the relay at the rear of the vehicle for the brake lights clicking on and off, I noticed that there was some creaking and groaning that seemed to be coming from the front of the truck as it's slowing to a stop. I pulled the front wheels of, and my inner brake pads on both sides were pretty thin, and the one of the driver's side was cracked. I replaced the pads, but the problem is still with me.

It seems like the brake light switch depends on a certain amount of resistance from the push-rod to activate. My guess is that for whatever reason, my brakes are softer than they should be right now, and it takes much more force on the pedal to activate the light switch than it does to stop the truck. If you press the pedal in a couple of times without the engine running to build up pressure, the lights seem to operate normally.

I'm thinking that the master cylinder might be leaking internally. It seems that this could cause a light pedal (not as much back-pressure on the pedal if the piston is leaking). It might explain the creaking also if the master cylinder is allowing enough pressure relief from the system that the brake pads are pulsing against the rotor.

Opinions? Thoughts? Help!

 

One more bit of information. The rear brakes are adjusted properly. I just checked the adjustment, and everything seems fine.

Can anyone think of something that could be causing my problem other that the master cylinder?

Thanks