Archived Mushy Brakes

[riley_d_sullivan]

I got a 2000 model with some brake problems. I was driving on the highway today and as I got to my destination, I noticed that the brake pedal felt like it went a little further than usual. I dismissed it as something I had never noticed before. As I drove around at low speeds through a residential area they became softer over about a 5 mile distance. Now they are very mushy even though I can still stop pretty well, but the pedal goes really close to the floorboard. I'm in Houston where there are no hills and I wasn't braking hard. I bled the brakes this afternoon and there was no air. I used Dot 3 fluid from Coastal last time I flushed the lines. The problem is bad enough that I'm not going to drive thetruck until it's fixed.



-Nervous

 

[riley_d_sullivan]

I looked at the vacuum lines and just went for a test drive to see if the cruise control still works. Works great. This may rule out a vacuum leak. I forgot to mention that my ABS and Brake lights are on. They both came on after the brakes got to the worst point. Brakes are hard when the pedal gets close to the floor. They don't seem to be getting any worse. Still scared to drive it.



-Still Nervous

 

[MidwestMotorman]

master cylinder???

Maybe the master cylinder? Take a close look at the fluid levels in each chamber and take for a drive or test drive it in your driveway with many brake applications. Check your brake fluid level again and see if one went down and the other went up. You could also have a bad master cylinder and not have the fluid cross the reserviors.

 

[riley_d_sullivan]

Thanks for the advice. One of the chambers in the master cylinder was rising while the other was going down. Somehow it was bypassing fluid. Replaced it with a new one. Good as new.