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Discussion Starter · #1 ·
I hate the brakes on my 96 ss. I have a severe vibration when I hit'em hard above 40 almost rips the wheel outa my hands. I've looked at them but everything looks ok. so I figure it badly warped rotors, defenitly on my short list. But my question is when I touch the pedal it seems to travel a bit before anything happens, fluid level is ok, pads are ok, there is a hissing sound but once I finally feel some presure it seems to stop ok except for the vibration.
Any suggestions?
 
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Discussion Starter · #2 ·
Read this thread that's running now in Brakes.
Click on, "I hear a spring kind of noise And Gliding stop at times".
Read my post on inspecting for seized Rear Sliding Pins. This is probably cause of low petal.

The vibration is either warped Front Rotors or faulty Caliper.
:eek: For safety sake, GET YOUR FRONT/REAR BRAKES DIAGNOSED/REPAIRED ASAP!!!!! :eek:
 
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Discussion Starter · #3 ·
Thanks that really helps, I'll look at the rear brakes in the morning. What would I look for with the front caliper's. The pads are about 25% wore I didn't notice any uneven wear or any pulling when they are applied. I'm pretty sure its the rotors.
 
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Discussion Starter · #4 ·
Could use more info about;
mileage of car,
are Rotors original,
were Rotors ever resurfaced, if so how many times,
your driving habits, i.e. conservative or abusive.

And, did you do last brake job[fronts]?
 
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Discussion Starter · #5 ·
I bought the car a month ago, 98k now has 102k.
I have done all maintnence listed in the manual,
just from looking at the rotors they look original. They look pretty thick still haven't measured them though. Still has the stock shocks etc on it Can't tell how much or if any maintnence was done to the the car. My best guess is they just threw some pads at it and didn't turn the rotors. probably put the rims on with an impact and didn't tourqe them, first time I removed them I really had use some muscle to get'em off. thru the week I commute maybe 2 miles to work so I'm pretty easy on it. But on the weekends I usually take a nice long ride on the back roads and really put it thru its paces. It really only shows itself during very hard braking at speeds above 40 the rest of the time it's not an issue. I wanted to save up and buy some croossed drilled rotors so i'll just take it easy on it until then. I like to do all of the work on my cars, I have had a hard time finding a shop around here that I trust or like :rolleyes: I'm fairly compitant with a wrench just don't ask me to do any body work.
 
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Discussion Starter · #6 ·
You can't tell if they're warped by looking at them, you need a runout dial gauge to check that. Your rear slide pins are probably frozen, so that's why your pedal is going to the floor. Time for a major brake job.
 
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Discussion Starter · #7 ·
Originally posted by nicksta43:
I have a severe vibration when I hit'em hard above 40 almost rips the wheel outa my hands.
Dumb question, but what's the chance that your "severe vibration" is the ABS activating?
 
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Discussion Starter · #8 ·
Dumb question, but what's the chance that your "severe vibration" is the ABS activating?
not even close to locking up. I do feel it at slower speeds just not as bad, it's like when you come to a light that just changed to yellow and decide to stop rather than go so you have to stop a lot faster than you normally would. I might have over stated how bad it is just a little.
 
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Discussion Starter · #9 ·
I would inspect things to make sure the calipers are in good working order. Also inspect the rotors closely and make sure you don't have severe radial cracks. Very small surface cracks are ok.

Some causes of warpage aren't necessarily physical warpage (the kind that's cured on a lathe) but a change in the temper of the metal as the rotor rotates (that turning the rotor wouldn't even fix). This gives an ever-changing coefficient of friction and feels like warpage. If your brake pedal doesn't vibrate in time with the vibration you feel as you slow down you might have the heat tempering problem (caused by uneven cooling). You could attempt to fix this by really heating up your rotors. Accelerate to 100 and stop HARD (but not ABS) down to about 20mph and do it again. Maybe a 3rd time. After this, try not to stop for a few minutes to let things cool down evenly (this is crucial). You may like the results (or not).
 
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Discussion Starter · #10 ·
Some causes of warpage aren't necessarily physical warpage (the kind that's cured on a lathe) but a change in the temper of the metal as the rotor rotates (that turning the rotor wouldn't even fix). This gives an ever-changing coefficient of friction and feels like warpage. If your brake pedal doesn't vibrate in time with the vibration you feel as you slow down you might have the heat tempering problem (caused by uneven cooling).
Thanks for the info. I really don't notice it in the pedal though, from slower speeds the car seems to surge wich would seem to fit your theory.
But at higher speeds I definetly notice it in the wheel. I think I'm going to save up and do the whole b/s with new cross drilled rotors, steel braided lines and some good pads.
 
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Discussion Starter · #11 ·
Originally posted by nicksta43:
Thanks for the info. I really don't notice it in the pedal though, from slower speeds the car seems to surge wich would seem to fit your theory. But at higher speeds I definetly notice it in the wheel.
You'd notice it in the wheel even if it was caused by physical warpage. You have the right and left front pads/rotors constantly applying an ever-changing force to the car, and the left side might be braking harder one second (or fraction of a second) then the right side might brake harder. You'd certainly feel that in the wheel, especially at higher speeds where the frequency of this uneven-ness increases.


I think I'm going to save up and do the whole b/s with new cross drilled rotors, steel braided lines and some good pads.
Uh-oh. Drilled for what purpose? Looks? Performance? I think some members here (who are quite a bit more knowledgable than myself) could explain why drilled isn't want to do if you are looking for performance, fade-resistance, durability or pad life. Just for looks is an ok reason, if you do just street driving, though...
 
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Discussion Starter · #12 ·
O.K. maybe I watch too much t.v.
But thats why I asked the question, so I could learn from everybody else's mistakes

Just kidding, I'll do a search for them and see what turns up. Thanks for sharing the knowledge :D
 
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