on a 97 legacy L wagon ,with abs, all of a sudden the pedal is alittle low, no abs light on , brake fluid good, the pads / rotors good , aleast half the pads left, any thing to look at first ? thanks

if you can, get it in the air and check for any leaks if none are visable i would bleed the brakes and see how it feels........by the way how does the brake fluid look?

fluid looks ok, but not real clear, when i changed the front axles there were no leaks then 5,000mi ago , but have not checked the back , thats what i was thinking about doing bleeding the brakes and put in all new fluid ,thanks

On an eleven year old car, it might be a good idea to install a new master cylinder, then bleed out the system. I don't think this has anything to do with your abs.

if the master cyl looses 1 part of its 2 part system it could couse the pedal to do this,i would bleed the brakes first, then if that doesnt do it, replace master and rebleed untill all fluid is clean and new, that should do the trick....

ok, it has 156,000mi on it,

You mentioned you changed axles. Make sure those axle nuts are tight. I had one back off I me one time. Don't know how, it looked staked really good. It took quite awhile for it to happened. Anyway the outside pad was worn way down from the wheel trying to get off the shaft. The brake pedal felt lower than normal but still firm. As mentioned your master maybe starting to leak internally, you won't see the leak but you'll feel it in the pedal.

Pump the brakes till they get hard, then press hard if they don't stay frim for a few seconds I'd suspect the master.

what i need notice when i changed both axles ,was that the axle nuts were pretty loose, what is the right way to change a master cylinder, ? thanks

bench bleed the new one first, then it will onlu need a little bleeding to get the air out when installed,have help to bleed brakes and bleed the chit out of them

Haynes manual has a generalized bench bleed procedure if you need it.

Or do a Google search on "bench bleeding"; there are a lot of online articles.

Also, to minimize the chance of damage to the brake line fittings, you might want to get a properly-sized tubing wrench if you don't already have one.

Good point. Also I have noticed at least the crapsman flare/line wrenches will open up a bit if you start really laying on them thus can potentially round off the nut. I clamp some vise grips onto the line wrench open end after getting it on the fitting so that it stays nice and tight.

ok thanks

I wouldnt buy a master cyclinder yet, most of the time I have had a master cyclinder go bad the pedal is not low but the brakes must be pumped in order to mantain the pressure.

 

I think your problem may be a bad caliper or wheel cyclinder letting pressure leak off, it can do this without showing fluild leak.

 

For just a few dollars you can buy a brake line pincher from Snap On and then you can check each caliper, if one is bad when you pinch that line you will mantain the brake pedal.

 

The reason I say this is because I chased this same problem and changed the master cyclinder and it did not fix it, I then took it to Midas and they found it was the front caliper by doing the above test.

Another thing that can cause this is a

bad wheel bearing.

 

The hub/rotor floats around and pushes the pads

back into the caliper.

 

Next time you step on the brake the

pad must first move this distance before

contacting the rotor,

 

thus the lower than normal pedal.

ok thanks