Brake sticking question...

[farley556]

My front brakes are sticking sometimes really bad to like where i have to pull the car over and sometimes just a little bit. When they stick, i will take my foot off the brake pedal and it doesnt come back up all the way. Usally I can just tap the brake pedal and they will unstick. Also sometimes when I turn they will stick as well. Started happening right after I got new brakes (pads, rotors turned).

Also I got a new parking brake cable put in and after that got installed I started hearing this wooo sound (not constant) from the back right brake. You can only hear when you are going slow (like 5-10 mph), Usally after i get off the express way or been driving for a while. It feels like nothing is right.

Any suggestions on whats wrong or what I should do?

Thanks.

 

[MO-KAN SHO]

if you had the brake work done somewhere, I'd take it back to them...

as for the ebrake cable, is it possible it's too tight and is dragging? I'm pretty sure the two problems are different issues, but if you did the work yourself, it my be worth taking the wheels off and making sure nothing is binding the ebrake cable or anything like that.

I don't know enough about hydraulic brake systems to know why they might be sticking. I'm sure someone else will be more help on that. Or the ebrake cable to for that matter

 

[farley556]

re brakes

I already took it back to them but they said they could find anything wrong with it, but it still keeps doing the same thing.

 

[jedhead]

The spring inside the brake booster that returns the brake pedal back up has weakened over time. The cure is replacing the brake booster.

Bob

 

[rangerj]

556,

Here are some thoughts for you.

Based upon the description of the problem you are having I would try the following;

1. The master cylinder has two pressure relief holes, one for each part of the "duel safety master cylinder". As you release the pressure on the brake pedal the brake fluid should squirt up into the resivoir, or at least cause the fluid in the resivoir to swirl, due to the release of pressure and the return of the fluid to the resivoir.

Have an assistant apply and release the brake pedal. When the pedal is released you should see the fluid return to the resivoir.
If the fluid is not returning to the resivoir, or returns with very little "stirring" of the fluid, then the hole is plugged (partially or completely).

If these holes are plugged up the pressure on the brakes is not released, thus they will drag. If one hole is plugged then one front and one back brake will drag. (The master cylinder is split so that pressure is applied to one front brake and the opposite rear brake by each of the two sections)

Use a small piece of wire to clean out the holes, but be careful not to get anything stuck in the master cylinder.

2. You could have brake calipers that have the pistons "cocked" in the bores and sticking. Having more than one stuck at the same time would be unusual but it does happen. This would necessitate replacing the calipers.

3. You may have a broken brake pedal return spring, or the return spring has become weak due to age. This would not cause the brakes to stay applied, so it would be a seperate problem. This is a relatively common problem and requires replacing the pedal return spring. (Under the dash)

4. The rear wheels should spin freely when the emergency( or parking) brake is OFF. There will be a little drag on the brake disk because there is a small amount of static pressure on the brake lines at all times, but it should not make the wheel hard to turn. If the wheel is hard to turn and the pressure relief holes are clear, then check your emergency brake cable adjustment.

5. You could have brake hoses that are swollen on the inside (due to age or contamination) and not releasing the brake pressure. This is also a common problem and would require the replacement of the rubber brake hoses.

6. It would be a good idea to pump fresh brake fluid through you brake lines if it has not been done for more than a couple of years. The recommendation is to do this at least every two to three years.

Use a brake fluid that is a "Low Moisture Activity" brake fluid such as Castrol LMA, or ATE "Blue" or ATE "Gold".
(ATE is the brake fluid recommended for BMWs). The aforementioned brake fluids are LMA fluids, and have high heat ranges. Ford also has a high performance brake fluid, but it is expensive and usually has to be ordered.
Interestingly enough most Ford dealership mechanics do not know about this!

NOTE: the recommended brake fluid is DOT 3. DOT 4 is a higher heat range fluid and is perfectly compatable with our brake systems. DO NOT EVEN THINK ABOUT DOT 5 (silicone fluid) as it is NOT compatible with the system components (period).
Just some thoughts, rangerj

 

[Rockledge]

I had a very similar "woo" sound from the rear of my SHO, and when I recently serviced my brakes, one of the slide pins on the driver's side rear was dry and crusty and in all liklihood was causing the caliper to stick, since I have not heard the sound since I took the pins off and cleaned and re-lubed them a few weeks ago. So that is something to consider. I would also want to look over the slide pins on the front brakes based on the same reasoning.

However, the fact that a parking brake cable was recently replaced makes me suspicious that it might be the source of the sound, like for example maybe the cable is installed improperly, or is sticking itself and thereby not releasing the caliper completely.

In any case, it's time to start pulling the wheels off and looking things over real good.

 

[rangerj]

Rockledge makes an excelent point. The slider pins will also cause sticky brake problems. Add that to the list. The slider pins should be clean and free of corrosion and/or crud and greased with silicone grease. Good catch rockledge. rangerj

 

[Howdy_Doody]

As for the brake sticking problem, I had a 92 that had the same problem. The dealer told me that Ford had a problem with the brake boosters but never recalled them. He quoted me over $400 to replace. There may be a TSB on this...I thought this was a fairly widespread problem.

My solution was to rig up a light spring between the pedal and the dash. Make sure it is light enough that it doesn't affect actuation of the ABS. Just enough to return the pedal properly. Drove it like that for over a year without a hitch.

Do something about this because you will wear out your front brakes fast!