Brake question................What do you all think?
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Race Director
Joined: Jul 2001
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From: So Cal
Brake question................What do you all think?
I have a 94' auto with about 90k on her. It has new front slotted rotors and new pads all the way around. Brake fluid level is good, but no matter how hard I mash the break pedal I can't get it to lock up or the ABS too kick. The pedal is not mushy or soft, but I don't feel the brakes are powerful enough. Any suggestions. Is this normal or is the Master Cylinder going out? :confused: Any help is appreciated and thank you in advance. :cheers:
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Re: Brake question................What do you all think? (morphious)
Kinda sounds like the Master Cylinder to me, bleed them too.
Melting Slicks
Joined: Sep 2000
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From: Carlsbad, CA CA
Re: Brake question................What do you all think? (morphious)
do you have the standard or the J55s? If you just have the 12" standard brakes I would get rid of those ASAP! Upgrade to at least J55s or C-5s.
When I drove my car with the standard brakes I thought there was something wrong too, it just doesn't want to stop, especially after a couple of high speed stops.
Your ABS should work, and if it doesn't it's got to be something wrong with the ABS module and not the actual brakes.
To check if your ABS works I would do this roll your car at around 20 mph and just JAM on the brakes, the ABS should definitely activate.
I would also check for the following things. Check if your Master cylinder is leaking from the back, see if there are traces of fluid dripping down.
Replace all the brake hoses with SS lines and get the bias spring. At around 90K your plastic hoses should be replaced. The SS lines will not expand when pressure is applied so you will have a firmer feel.
The bias spring will get your Corvette 60/40 bias compared to 70/30.
Check to see if your fluids are clear, without much containmination in the fluid. If it is dirty or muddy, bleed your fluid and replace with the Ford HD fluid.
Check for those things if you can't upgrade your brakes.
When I drove my car with the standard brakes I thought there was something wrong too, it just doesn't want to stop, especially after a couple of high speed stops.
Your ABS should work, and if it doesn't it's got to be something wrong with the ABS module and not the actual brakes.
To check if your ABS works I would do this roll your car at around 20 mph and just JAM on the brakes, the ABS should definitely activate.
I would also check for the following things. Check if your Master cylinder is leaking from the back, see if there are traces of fluid dripping down.
Replace all the brake hoses with SS lines and get the bias spring. At around 90K your plastic hoses should be replaced. The SS lines will not expand when pressure is applied so you will have a firmer feel.
The bias spring will get your Corvette 60/40 bias compared to 70/30.
Check to see if your fluids are clear, without much containmination in the fluid. If it is dirty or muddy, bleed your fluid and replace with the Ford HD fluid.
Check for those things if you can't upgrade your brakes.
Burning Brakes
Joined: Sep 2001
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From: Jupiter Florida
Re: Brake question................What do you all think? (morphious)
If the level is holding you're probably not leaking, so I might guess that you're getting some fluid past the o-rings in the master cylinder.
These things run completely wonky if the booster vacuum line is leaking, you'd probably notice that.
A torn booster diaphragm will have symptoms similar to what you're describing, but there will be an audible hiss when you apply the brakes.
Galactic PITA the replace those thing BTW, hope it ain't that.
These things run completely wonky if the booster vacuum line is leaking, you'd probably notice that.
A torn booster diaphragm will have symptoms similar to what you're describing, but there will be an audible hiss when you apply the brakes.
Galactic PITA the replace those thing BTW, hope it ain't that.
Thread Starter
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From: So Cal
Re: Brake question................What do you all think? (rocketfinger)
I don't think my ABS is bad it just feels like the brakes don't grab enough to set ABS off. :confused: I do want to replace the lines, but would like to do everything at once.
Heel & Toe
Joined: Jul 2002
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From: Whiteville NC
Re: Brake question................What do you all think? (morphious)
I just bought an '84 'Vette I'm working on now. When I got the car, the brake pedal would go almost to the floor. I thought I needed a whole new brake job (pads, rotors, etc.), but I found I had a slow leak in the master cylinder. Got a new MC at NAPA for $73, and when I put it on, brakes were like new....full pedal and great stopping. Not saying for sure that's your problem, but a new MC isn't too expensive and could cure the issue with your brakes. Good luck!
Tom C
Tom C
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Thread Starter
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From: So Cal
Re: Brake question................What do you all think? (jefft84)
Not sure about bedding, but the calipers were rebuilt and everything as far as calipers, pads, rotors are working fine.
Le Mans Master
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From: And on the fifth day, subpoenas were served to Obama senior staff
Re: Brake question................What do you all think? (morphious)
Not sure about bedding, but the calipers were rebuilt and everything as far as calipers, pads, rotors are working fine.
What kind of pad did you use?