brakes dont work correct when wet

After the jeep has been sitting (parked) in the rain for any given ammount of time, the brakes dont work the first time I go to stop. It is like I am tring to stop on ice or somthing. They work fine after the first time I try to stop. It only happens when it has been raining. And it cant be ABS related because I pulled the fuses and it still happened. I have gotten used to it as it has done it for the past year but I think I need to look in to fixing it sooner or later.. Any ideas??

Thanks
Chris

EDIT: 1992 XJ 4.0L w/ ABS

I have the opposite problem. After it has been sitting for a while in wet weather the first time I touch the breaks the front tires instantly lock up.

bzdel2441 said:

After the jeep has been sitting (parked) in the rain for any given ammount of time, the brakes dont work the first time I go to stop. It is like I am tring to stop on ice or somthing. They work fine after the first time I try to stop. It only happens when it has been raining. And it cant be ABS related because I pulled the fuses and it still happened. I have gotten used to it as it has done it for the past year but I think I need to look in to fixing it sooner or later.. Any ideas??

Thanks
Chris

EDIT: 1992 XJ 4.0L w/ ABS

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Have you ever adjusted the rear brakes? I ask because that's normal for disc brakes when they get wet, it takes a few braking cycles to dry them off. Adjusting the rear brakes to make them work more effectivly would allow better stopping performance until the fronts were dry. I can't really think of anything that would make the brakes only lose pressure when wet. The best thing to do is just go through the whole system and inspect it. Make sure it's not losing fluid, check the rubber hoses and hard lines, make sure calipers aren't stuck or dirty, adjust and inspect the rear drums.

The common problem is a rear brake locking up at a touch when damp. Threads on this occur periodically. Theories abound. Mine do this intermittently. Adjusting them helps a lot.

The self adjusters on these brakes are awful. If you're having trouble with the rears, it's probably a good idea to assume from the start that the adjusters have failed.

I solve the problem on my NON ABS 98 by putting my foot gently on the brake pedal and riding it for a few hundred feet to the stop sign down the street. Every once I a while I forget and go to stop which locks up the rears. This problem on an ABS vehicle might be confusing the ABS system when the rear brakes lockup and the ABS releases them...never been a fan of ABS myself..

What Pads and Rotors do you have? And what condition are they in?

Wet rotors and pads will have a tough time stopping, especially when cold. Usually the first stop scrapes off the excess water and warms up the rotors/pads enough that the subseqent stops are normal.

Cheap Pads and Rotors are more likely to do this than better quality versions, as well, worn and uneven pads/rotors, even bad guide pins, bushings and gummed up rails contribute.

I never buy less then the mid-quality pads, the importance of brakes is more than worth spending the extra $25-$35 dollars on the mid to high quality pads. Never buy the $18 pads at your local big auto franchise. These will squeel no matter how good of a brake job you do, have a longer stopping distance and general poor performance, like very bad performance when wet.

fbueller99 said:

I have the opposite problem. After it has been sitting for a while in wet weather the first time I touch the breaks the front tires instantly lock up.

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mine has this same problem

same problem here...NON ABS 99. Ended up having to replace the rear shoes b/c they became worn out and the problem went away. That was around November(ish)....4 months and one decent accident later and they're starting to do it again. Just something to get used to. I usually leave the e-brake one or two clicks up instead of putting it down all the way in the mornings till i get to the end of my street (about 1000 feet). The brand I have on now are just the regular Napa brand shoes. I also have Napa pads and rotors on the front and havent had a single problem out of them.

99XJSPORT06 said:

same problem here...NON ABS 99. Ended up having to replace the rear shoes b/c they became worn out and the problem went away. That was around November(ish)....4 months and one decent accident later and they're starting to do it again. Just something to get used to. I usually leave the e-brake one or two clicks up instead of putting it down all the way in the mornings till i get to the end of my street (about 1000 feet). The brand I have on now are just the regular Napa brand shoes. I also have Napa pads and rotors on the front and havent had a single problem out of them.

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If leaving the parking brake a couple of notches up helps, I am guessing so will a good manual adjustment.

My 95 had the opposite problem (rears locking very easily when wet). Changed shoes and drums and the problem went away.