2001 Sport Trac brake fluid disappearing

[crobyhop]

Had a leaking master cylinder which was replaced. A short time later I found the fluid low again. Mechanic couldn't find any evidence of leaking anywhere. A short time later, the same thing happened again. It is not dripping on the driveway. Any ideas about WHERE the fluid could be going?

 

[sandsprayer]

How low, and what is the time frame/miles driven?

 

[Josh P]

Is the master cylinder new or a re-manufactured part? Did you change the vacuum booster with the master cylinder? brake fluid kills them then they like to suck fluid.

 

[sandsprayer]

Did you change the vacuum booster with the master cylinder? brake fluid kills them then they like to suck fluid.

That's where I was going!

 

[crobyhop]

How low, and what is the time frame/miles driven?

3 months. Only 500 miles. About an inch below MAX.

 

[sandsprayer]

Start out with what @Josh P was asking. See if the seal is allowing it into the booster

 

[410Fortune]

check the rear wheel cylinders, that is the first place a brake fluid leak will develop, it is quite possible your mechanic missed it?
Also look at the bottom of the brake booster, under the MC< is it wet?

 

[sandsprayer]

Start out with what @Josh P was asking. See if the seal is allowing it into the booster

use the smell test by pulling the vacuum hose