97 lumina brake problems

[justinWants2know]

I've had alot of problems with losing my brakes. It seems to happen when its a change in the weather. I've also had 2 master cylinders in 5 years, vibration in the brakes.

[jeffcoslacker]

Leaks in seals can cause brakes to react to changes in humidity mostly, as they allow water to be drawn into the fluid from the external air. You need to take the back drums off, if you have disc/drum brakes, and verify that the rear wheel cylinders are not leaking. This is usually the most likely place to draw in humidity. You may want to replace the master cylinder cap, and I would have the fluid flushed and replaced, to rid the system of any moisture and worn out fluid. If you have had a situation that caused the brakes to run hot, the fluid is toast. Once you have rid the system of any air, moisture and bad fluid, you can see if the operation improves, or if more work is neccessary. Check the torque on your lugnuts for 100 ft lbs, excessive or uneven torque can bend rotors out of shape and cause pedal hop.