Brakes

[B-Cack]

Just replaced rotors, pads, master cylinder, and power boost unit. yet my Brakes make this groaning sound when coming to a full stop. Then the right front brake seems to release and the Bronco will kind of move foreward and do this left to right dickdance..... it is the most peculiar thing. I have even seen three differnet brake shops and they can't find anything wrong. This is on a 93 XLT... anyone have any similar problems or and suggestions?

 

[Pony-boy]

Bearings, Caliper mount bolts, ABS ring missing a tooth. Thats about it

 

[Guest_B-Cack]

Yeah, I checked all that... darn thing is, everything looks just like it should. Maybe I will bleed them out once again....

 

[DragonDave]

Well this is a long shot. The last time I heard a car making a loud groan noise when you apply the brakes was because somthing had contaminated the rear shoes. ( in this case they used carb clean instead of brake clean) Changed the rear shoes & the noise went away. Did you get all the cosmoline off the new rotors etc? Thought i'd giver a shot. Let us know wat it was when u find it. Good Luck!

 

[Guest_B-Cack]

Dave,

Yeah that is good advice, but I am pretty sure the problem is occuring up front. This is weird, but I am telling you, it "feels" like something is just giving out when the brake pedal just about reaches the bottom.... and the funny thing is, it "feels" like it is only on the right front side, which causes her to shake maybe 5 inches foreward and right, while the left is solid. Thought for sure I nailed it when I replaced the power boost unit... but I will be damned, she is still at it... although not as bad. I am nearly at my wits end, even the mechanics can't figure it out. The only other thing I can think of is that I thought there was a valve of some sort that controls the flow from front to rear, and that sometimes this can get clogged open or shut or just go plain old tits up.... rggggggggg

 

[Ziggy]

The proportioning valve controls front and rear braking. Do you have ABS? Could be in the control module or sensor. You may have a warped rotor or loose bearing on one side. But a warped rotor will be felt in the brake peddle by a quick "grab and release" feel. When you bled the brakes, did you start at farthest point from the master cylinder and work your way forward (normally RH rear, LH rear, RH front and then LH front)? I've had this "groaning sound" before and I can't remember what was the cause or how I got rid of it, but I believe it was from contamination.

 

[Guest_B-Cack]

Zig Man,

My armed forces buddy. Yeah, I bled the brakes right, started with the farthest and all. I don't think it is a warped rotor, they are new, as well as the pads. It is the weirdest thing, I mean when you apply brakes, everything is going well ok... no problems, then as the pedal gets to about the bottom and I am almost stopped, it just feels like it lets go for a split second on the right front, gives a little shake and then POOF no problem. I can even get it to the point where I just about know it is going to get weak on me, let off the brake and then about a second or two later, apply it slowly and it is fine.... just damn irritating and I am not sure how safe this is.
I do have ABS by the way

 

[Ziggy]

ABS, great system till you have problems, then it drives you nuts. Best thing I can tell you is that Haynes puts out a real good book in dealing with ABS systems, troubleshooting and repair. Bought it for my van and pin pointed my problem in about 2 hours of reading and testing. Just because rortors are new, does not mean they can be warped. I always have mine "trued" just to make sure, takes about 20 minutes and $10.00, but worth it. What about the sensor for that side, check the wires and make sure they are not broken. Control module may be getting a false or intermittent signal.

By the way, I just replied to your other post with about the same response as what I gave you here about bleeding brakes, except I covered the master cylinder. Don't mind, keeps me on my toes and my mind occupied.

 

[Guest_B-Cack]

Yeah, I think I have a ghost post going on in here.

 

[Bronco Rob]

I just did the front and rear brakes on my truck because of this problem. The rear drums were shot completely. Here the previous owner had replaced a brakeline that wasn't OEM, and made it a bit longer than the old one, causing the right front brake to grab early and release late. Have ya checked your brake lines?

 

[Ziggy]

Length of replacement brake line shouldn't make a differance since your pushing a solid fluid (in theory). Besides, if it is longer, why would it grap early and release late? If anything, it would grap later and relaease later.

 

[Guest_B-Cack]

I haven't checked all the lines yet, was planning on bleeding it all out again. I will check to see if maybe there is a small leak or something..... I tell you what, this is a real pain in the ass