In my 89 firebird i have front disc rear drums brakes and one day the pedal just went down when sitting still and i lost my brakes. Had to change the master cylinder to fix the problem. What could have caused this? could it have been too much power braking? or just the use of brakes or wear from time?

 

the rubber seals are most likly the cause ... power braking may be hard on the drive train but id say it had little or no effect on the seals wearing out .... im no expert but i would bet im right ... if not sombody will speak up and set us stright ... good luck tao

 

the thing is that it wasnt leaking anywhere majorly that i could see up top. underneath the car was a bit of wetness but lead no trace to the top. ?

 

when you look at the amount of fluid in the system or the master cylender actually it dont take much fluid loss before it becomes a problem ... if the seals wear out on the master cyl. it can no longer build up pressure in the line ... although im not to sure where any fluid leaking past the piston would go .... on a side note brakes are highly over rated ... take care