i have an 89 trans am, it has a hard time stopping and cant lock up the wheels. the car has new brakes,rotors, front brake lines,master cylinder, power brake booster and it still does the same thing,any ideas, brakes have been bleed, master cylinder was bench bleed as well.

 

what brakes do you have? Disc/drum? Disc/disc? Does it not like to stop all the time, or just after a few hard stops?

 

4 wheel disc and always has the problem.

 

struts and shocks?!?!?!

 

I had a 92 RS with a disc/drum setup. I also thought that it stopped like crap. I swapped to a 1LE setup at all four corners. I can put you through the windshield at will.

If you have the iron rear calipers, they are for suck. they are worse than drums. The PBR aluminum calipers are much better. Which do you have?

You could always upgrade just the fronts which is fairly simple and took me about 2 hours to do with help.

I don't know if that helps any, but I can only speak from my own experience.

 

It has newer struts and shocks but even if they needed replacement the car wouldnt brake as bad as it is now.

 

Do you have iron calipers in the rear?

 

rears are aluminum

 

Dam, dude. My paw had a 89 silverado that did the same thing, he took it to the dealer several times, then to about 10 different garages. Everything was changed, the booster, master cylender, hardlines, rotors, pads, prop valve, and more. He ownes the truck to this day, and it still can't lock the tires. The chevy dealership in town told him that he "didn't know how to use the brakes."

I don't know, I hope someone can help. Before I did my swap, My RS stopped like hell but if I layed on the brakes, I could get them to lock up.

 

I have had the car parked for about 2 years and I dont remember it being that bad, but i sure wasnt good even then, I now that that back then I had the car on jacks and the rear wheels would still spin with the foot on the brake and would only completly stop when I stood on the brake. Even if the rears arent working properly the fronts should still lock up or am I wrong.

 

i was messing around in my driveway with a few friends and they were sitting on the hood and stuff and i would go like 10 and slam on the brakes and try to make them fall off. lol good times. my brakes lock up good all stock. left skid marks in the driveway...

 

my brakes are the same that came on my car, 800$ Heap, working on it atm.. lol


they lock up no problem at all * somethings wrong there*

 

Does your parking brake work? It should be able to hold the car in gear at idle. I had the same problem with my PBRs this summer. Pulled them off and did a rebuild. The lube for the pins the calipers slide on had dried to nearly dust, and the pistons were sticking in the bore. They work great after the rebuild, parking brake included. Sounds like time for a rebuild.

 

Reconsider those "good" times.

I agree with Wheel: sounds like rebuild time.

JamesC

 

y's that?

 

Safety. Youth and decision-making sometimes yields bad results. But then, for that matter, so does age and decision-making.

JamesC

 

well you know i could have been doing something a lot worse...like taking my car for a ride on the highway with my 2 buddys and driving crazy...you get my point? i know what your saying but i dont think what i was doing was that big of a deal

 

And therein lies the problem. Enough said. Enjoy your car.

JamesC

 

Lol, Thanks to fooling around my " jewls" Hurt today

Was pushing a car into shop kid jammed onto the brakes when we were going like 10 or so, didnt see it coming....

i flew into the wing and banged myself up pretty good, was fun besides my "valuables" getting nailed by a chevy cavalier

o well its all in good fun, sorry for highjacking!

 

When did you do all the repair work, after it was sitting for 2 years or before? How does the pedal feel, hard or soft? Did you replace the brake hoses? These swell over time and the passage gets real small over time.

Assuming that you did it after, 1 item overlooked is the proporting vlave. A lot of GM cars use the proportioning valve as a fail safe device. The Proportioning vlave is also know as a balancing vlave. If this vlave is forced too far to one end, front or rear, you won't get fluid out when you bleed or get pressure to the brakes when you step on them.

The purprose of this feature is that if the rear or front brake lines have a ruture in the line the propotion vlave will "slam" shut and stop fluid from going out, but still maintian pressure to the other wheels. Yes, the master cylinder is dual but this keeps the fluidform running out of the resivoir.

You can tell if it not "centered" by the amount of fluid you are getting, if any, when you bleed the system. When you bleed the brakes, you may need to bleed the rear, then the front, then rear then front, etc. to balance the valve, then you can resume the standard bleed procedure. etc.

Also make sure the pads are GOOD pads not el cheapo pads and not glazed, the brake discs also. pads wil mkae a HUGE difference. Also the caliper should slide free, not bind.

With my PBR calipers front and rear and Hawk blues front and HP Plus rear, I can put myself through the windshield. The system is BONE stock etc. for pads and SS brake hoses.

Hope this helps and good luck!

Steve

 

I just installed a vacuum canister and the car brakes better but not great, I was able to lock them up but only about 2 out of the 8 tries. I dont have much time to work on the car but I going to check for any leaks at the canister and also will probably also change the brake hose or hoses(not sure if there 1 or 2,ill have to look at it) at the rear.

 

This isn't really true. The proportioning valve has nothing to do with seperating the front brakes from the rear. This is a function of the master cylinder. The only thing a proportioning valve does is limit brake pressure to the rear brakes to prevent them from locking up before the front brakes. This is half of the function of the combination valve found on our cars. The other half, the metering valve holds off applying the front brakes until a predetermined pressure is reached. This is to compensate for the distance the rear shoes have to travel to contact the drum.

I'm not saying the combo valve couldn't be your problem. I just don't want you to replace it for the wrong reason.