Sticking front brakes
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I noticed the other day that my front drivers side caliper was sticking.
Bad caliper I thought. I then purchased new calipers rotors and pads
and .... it still sticks. Not bad, just for about 5 seconds or so.
I noticed in the FMS that a series of valves operate the ABS.
Could one of these valves be sticking ? If so is this valve assembly rebuildable?
Any other ideas ?
JLathem
Bad caliper I thought. I then purchased new calipers rotors and pads
and .... it still sticks. Not bad, just for about 5 seconds or so.
I noticed in the FMS that a series of valves operate the ABS.
Could one of these valves be sticking ? If so is this valve assembly rebuildable?
Any other ideas ?
JLathem
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Originally Posted by jlathem
I noticed the other day that my front drivers side caliper was sticking.
Bad caliper I thought. I then purchased new calipers rotors and pads
and .... it still sticks. Not bad, just for about 5 seconds or so.
I noticed in the FMS that a series of valves operate the ABS.
Could one of these valves be sticking ? If so is this valve assembly rebuildable?
Any other ideas ?
JLathem
Bad caliper I thought. I then purchased new calipers rotors and pads
and .... it still sticks. Not bad, just for about 5 seconds or so.
I noticed in the FMS that a series of valves operate the ABS.
Could one of these valves be sticking ? If so is this valve assembly rebuildable?
Any other ideas ?
JLathem
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So you replaced BOTH calipers and the same left front caliper hangs up? I can't help you with the ABS part but I thought that it would through a code and the ABS light would stay on if there was a problem in the ABS system. Did you lubricate the slide bolts with some silicon grease before you inserted them into the calipers?
Thats why I think its in that valve assembly. I think. I'm going to tear into it today
and see what happens.
JLathem
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Originally Posted by jr's3800
Ol' Timer, do you think there would be a possibility of the brake line being collapsed causing the caliper to stick? I have seen this happen on many oldrer cars and trucks... Just a thought... Any ideas?
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DO NOT TAKE THE PMV APART. It'* not user servicable. That and when you actualy get to the solenoids all the wiring falls apart and you're screwed. If it'* onlly one wheel I doubt the PMV is doing it.
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Good guess from jr's3800 on the hydraulic hose.
I have had this problem before where the flexible rubber hose to the caliper looks OK on the outside, but internally the rubber delaminates and acts like a check valve. When you apply the brakes the little flap of rubber prevents the fluid from completely returning from the caliper and the piston will not retract in the bore. So the pads stick or drag.
The hoses were 10 years old in my case.
Don't mess with the ABS $$$$$$$$$$$$ !
I have had this problem before where the flexible rubber hose to the caliper looks OK on the outside, but internally the rubber delaminates and acts like a check valve. When you apply the brakes the little flap of rubber prevents the fluid from completely returning from the caliper and the piston will not retract in the bore. So the pads stick or drag.
The hoses were 10 years old in my case.
Don't mess with the ABS $$$$$$$$$$$$ !
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Sounds like several of you guys have had the experience of working on the PMV.
The lines are original. I like the delaminated lining theory. I may try that.
The lines look great ( on the outside ). I bled about a quart of fluid through them yesterday
and it didn't help.
Thanks for all the help guy'*.
JLathem
The lines are original. I like the delaminated lining theory. I may try that.
The lines look great ( on the outside ). I bled about a quart of fluid through them yesterday
and it didn't help.
Thanks for all the help guy'*.
JLathem
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Well, it'* not the hoses. Does anyone else have any ideas ? Also .. one more thing I noted yesterday during a panic stop. The car pulls first to the right a little then to the left when I REALLY get on the brakes hard. Is it the PMV ? I can't think of much else.
So far I have replaced Rotors, Pads, Calipers, lines. I have ran 2 quarts of fluid through the system. The only logical next step is the PMV right ? I bet that thing is gold plated ... $$$
JLathem
So far I have replaced Rotors, Pads, Calipers, lines. I have ran 2 quarts of fluid through the system. The only logical next step is the PMV right ? I bet that thing is gold plated ... $$$
JLathem
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Have you managed to cause you Antilock to kick in....? Also how hard do you have to hit the brakes to get the antilock to function...
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I'm wondering about the master cylinder.... But I won't tell you to replace it yet... Look at the rear of the Master cylinder where it meets the Brake Booster, and see if you are leaking any fluid...
JLathem