I bet u cant fix my problem

[kolew]

I have a '95 grand am coupe. The rear passenger brake locks up when I am about to come to a complete stop, and ONLY AFTER i've already slowed down most of the way(right before I come to COMPLETE stop). EVERYTHING has been replaced i.e. the wheel cylinder, brakes shoes, all hardware. The bearings were good and spun freely with plenty of grease. After all that I thought it might be the abs, so I unpluged them from the wheel directly. Now the abs light is on in my dash and it still locks up. Also, it leans to the driver side in the back when it locks up which doesnt make sense cause that wheel is fine. So, if you think you can fix my problem I am all ears. Good Luck. Drum brakes in rear.

[fourie]

drum or diskbrakes at rear

[crazy Jim]

believe it or not but usually when your drum brakes lock up it is because of brake fluid seeping onto them. You may have a defective wheel cylinder or maybe just a contaminated brake shoe.

[Scrapper]

well you need to get it leveled out first and then figure it out.....i'm sure not going to brake rite when it's leaning..dosn't that make since????? if it wasn't leaning then you would know 4 sure that's not causing you problems..like the guy said brake fluid but you said u checked that and changed wheel cylinders..but a grease seal would lock it up also..but really guy you need it levaled out thats 4 sure...

[xeroinfinity]

this happens alot with drum brakes on midsized cars.
Irregular pressure on the lines.

Even my 99 SE does it every once in a while.
Several things contribute to lockup.

Contaminant containment

I still see people push caliper pistons back to make room for new pads without first opening the bleeder. Sure, you could get away with that in the old days and maybe avoid having to bleed the system, but now there's a good chance you'll cause ABS problems by pumping sediment (a combination of rust and the ashy residue of burned glycol) ad watery fluid up into all those tiny passages, valves, and pistons.
As one brake parts company training, manager says, "If you get sediment up into a 4WAL, for example, and it jams a piston, you'll have to replace the unit, which is $1,150 dealer cost. Even a reman is $850." Of course, it's not always so bad. With some units you can use a scan tool to put the system into the self-utilization cycle and pump itself clean, but why take the risk?

Lots of authorities say that just cracking the bleeder isn't good enough, citing the fact that contaminants naturally accumulate at the bottom of the cylinder where the hose comes in. They recommend that you also clamp the hose using a suitable smooth-jawed tool, and we agree. If you're afraid that hose looks too whipped to survive clamping, you should be replacing it anyway.

Flush 'em out
This brings up fluid flushing, something the domestic car companies are just getting around to including on maintenance schedules (most foreign auto makers have done that for many years).
Not only are corrosion and contamination of intricate and expensive ABS hardware to be strenuously avoided, but the same goes for a typical four-wheel disc system, wherein the parking brake/self-adjustment mechanism is immersed. Another factor is the high operating temperatures encountered with semi-mets and FWD, which makes maintaining a high boiling point critical to safety. Fluid changes are cheap insurance. Depending on whom you talk to, recommended intervals range from one to three years. Our opinion? Two, max.

Since this is a relatively new service item that the average motorist has never heard of, you'll need a good approach if you're going to convince him to have it done and thus save him big bucks in the long run. First, pull the owner's manual out of the glove compartment and show him where it appears on the service interval chart. Explain how disastrously expensive internal corrosion can be, and mention that in Europe people do this almost as religiously as they change their oil. Also, you might want to keep those "Wet Check" brake fluid test strips handy, or you could invest in an electronic moisture detector.
Speaking of ABS, another thing to remember is that it's asking for trouble to start a brake job on a car so equipped if you don't have the right scan tool. With Delco VI and Bendix systems, to cite two prominent examples, if you do something that causes the anti-lock warning light to come on, you won't be able to turn it out. Also, it's easy to damage those delicate wheel speed sensors while doing brake work, or to cause metal particles to attach themselves to the magnet.
Either is likely to put the system into default, or make it go permanently into anti-lock mode (called "false modulation"), and turn on the warning lamp.
The most horrifying hydraulic-system error we can think of is letting a dangerously rusted line or chafed hose pass inspection. Call us paranoid about this subject if you want, but we had two total brake failures arrive at our shop within a few months of each other, one involving an accident, just because nobody had ever taker a look at those lines, and we once almost took an icy dip in Lake Michigan when a front hose blew. These are not the kinds of comebacks you want on your conscience.

Avoid ABS problems during routine brake service.
Motor Age; 2/1/2003; Buckley, Jay M.

Antilock braking systems (ABS) have had more of an impact on brake servicing than may seem obvious. And although most jobs are routine and your customer leaves satisfied, on occasion somebody will come back in to your shop with a complaint.
The most successful technicians have mastered the art of quick -- but complete -- installations. Most comebacks aren't the result of something intentionally done wrong, but may be caused by something being overlooked.
I get the following call at least once a day: "I just did a routine front brake reline and now the car's:
* ABS light is on.
* Brake pedal is low.
* Brakes are dragging.
* Pulling to the left/right."
These problems can be avoided by adopting some simple and very effective practices when performing brake service on an ABS-equipped vehicle. The number one cause on these problems is very simple, and to prevent it from happening, technicians need to modify the way they are currently doing a brake job.

It is extremely important to open the bleeder screw when compressing caliper pistons or wheel cylinders during routine brake maintenance. When a caliper piston is pushed in, brake fluid gets forced backward, up into the system. Since the caliper is the lowest point in the system, dirt and corrosion naturally accumulate there. When this grime and dirt finds its way into the HCU portion of the ABS system, it can cause valves to stick. This can lead to: a vehicle pulling one way or another; accumelators sticking open, which leads to low pedal; compensator ports pluging, which leads to dragging brakes; and of course, it can make the ABS light come on due to all of the above.

If technicians get in the habit of opening the bleeder when they compress the caliper piston, as well as selling customers a brake fluid flush, these problems will more than likely be prevented.

Another problem that concerns installers is when the ABS applies itself at low speed. Wheel speed sensors are magnetic. They can collect large amounts of debris from the road. Freshly turned rotors also can leave metal filings on the sensors, especially if an on-car brake lathe is used. The Honda Motor Go. actually recommends removing the sensors during rotor machining. We suggest cleaning the wheel speed sensors and tone rings during a brake job. This can help prevent false signals that can actuate the ABS system during low speed stops.
Brake technology, like everything else automotive, is changing constantly. By keeping up on changes like these, you're likely to avoid unneeded comebacks.

Jay M. Buckley Bendix Answerman and Brake Training Administrator Honeywell Friction Materials

So Flush that old stuff out till it runs clear.
A vacum device works best for this as it sucks out more debrie and moisture.

In the end you may have to replace the ABS modulator or your master cylinder to end the dragin wheel.

Good Luck

[crazy Jim]

Xero, how old were the cars that experienced the total brake failures, and had the lines ever been replaced?

[xeroinfinity]

I'm not certain on the years , that really depends alot of enviromental conditions, heat, cold, humidity, so the age of the car really isnt the issue. It was around the time ABS was starting to be used in the US.

The only reason to replace a line would be if its smashed, bent/kinked, or rusted, etc etc. These too are all effected by enviroment conditions, and driving conditions.

Bad brake service is pretty common if the individual doesnt know how the system works, and how to properly maintain the brake system.

[Scrapper]

yes but would you take someone else life in your hands by not replacing whole line...instead of nowing for sure that it's fixed rite...you the that sais couple it together..

[xeroinfinity]

Originally Posted by Scrapper

yes but would you take someone else life in your hands by not replacing whole line...instead of nowing for sure that it's fixed rite...you the that sais couple it together..

you been drinking ?
......that makes no sense

But to answer about the life taking, thiers more to it then just replacing the line.

First off the replacment of "A" line isnt good.
If youre going to replace a line,
you should replace ALL of the lines.

Doing this will ensure the ABS modulator applys brake line pressure evenly to the wheel cylinders.
It all has to be balanced out so you dont get the lock-up.

Thier should be around 1200 psi at each wheel cylinder when the brakes are applied.
So if one locks up and the others dont,
then thiers a problem that needs adressed by a professional who's dealt with this before

And about the leaning,
I'd say you have a bad or weak spring in the rear,
or it could be cracked/broken
The upper strut suports can crack and break on this model of GA.

Which this could be why the rear is locking up too .


Hope this helped kolew