Bobcat698

I was driving in town and all of a sudden my brake pedal had to be pushed down MUCH farther to activate the brakes...

They did still work though. I have been running DOT 5.1 fluid and it was topped off about 2 weeks ago. I checked it when I got home and the resovoir was well below the ADD mark... So where did the fluid go if I cannot find any obvious leaks down by the calipers?

Also, the master cylinder has been replaced not too long ago by the previous owner.


Thanks!

timeagain

Try your antilock brake mod. & typ 5 fluid sucks up water like a sponge!! I used it in my bike once, had to replace the everything.

Bobcat698

Antilock brake mod?

fschiola

Had a tech friend tell me just the other day that DOT 3 and DOT 5 are not compatable.

Bobcat698

I have not mixed the 2 fluids. The previous owner used DOT 5.1 and gave me a few extra cans to use.. Then I had to add some when I did my front brakes again.

What would the fluid type have to do with my fluid dissappearing?

Bobcat698

Just filled the container to the FULL mark with DOT 5.1 again.. Pedal still requires a LOT of travel to get brakes. Brakes work well though when fully depressed.

Since the fluid was run so low, is it possible I need to bleed at all 4 corners?

Thanks

Bobcat698

Went about 30 miles with a full resovoir of DOT 5.1.. Its still full and the brakes are still as mushy as ever..

2500CTD

I would bleed them, and check the rear drums. They might need adjusting. Too much play in the rear drums will cause the pedal to drop. As far as lost fluid

Bobcat698

Hmm... That wouldn't be my problem.. I have rear disc brakes....

Thanks for the info.

2500CTD

Sorry about that! If I remember right Dot 5 doesn't absorb water. Not sure about 5.1? Also IIRC water is heavy and will collect at the wheels cylinders, and since water boils much lower temp than brake fluid........You would have to compress the "air" at the wheels.

Bobcat698

Found problem. Right front caliper where break hose connect decided to spring a leak.
It seems every time I fix a leak on this truck, ANOTHER ONE springs up

2500CTD

That is to keep you on your toes and ready for anything! Glad you found it.