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Having some braking problems. Anyone had a similar issue?

  • Thread starter Thread starter stang8urimport
  • Start date Start date Jul 19, 2007
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stang8urimport

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Jul 19, 2007
#1
  • Jul 19, 2007
  • #1
k, last thing a tech wants to do is ask for help on the internet, but oh well. I'm having some braking problems with my 90. I can push the brake pedal as hard as I can and it will NOT lock the brakes up. Driving around town it is normal, but in a panic stop, it feels like there is only about 70% of the braking power. I almost got in an accident the other day on the highway when someone panic stopped in front of me... Almost hit them in the rear. I've adjusted up the rear brakes, bled the system... I've even replaced the master cylinder to no avail. Only other thing I can think of is the hoses are balooning a little bit under extreme pressure. Any ideas would be helpful.

Thanks,
Nick
 

samickguy15

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Jul 19, 2007
#2
  • Jul 19, 2007
  • #2
Well the good part is they're not locking. When they lock up your braking power is reduced alot. I might suspect something is up with either the hoses or proportioning valve. When is the last time you looked at the pads??? Could be an issue there...
 

fivespeedsteed

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#3
  • Jul 19, 2007
  • #3
get stainless brake lines. its a performance gain anyways. balooning i wouldnt think would be it, because even still it would skid for a while before they ballooned that bad.
 

stang8urimport

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#4
  • Jul 19, 2007
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Pads and everything are new. And I understand that locking them up isn't good.. but it SHOULD be able to. The fact that it won't even come close to is bad. Any more ideas?
 

fivespeedsteed

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#5
  • Jul 19, 2007
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proportioning valve? other than that i dont know.
 

Fett

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#6
  • Jul 19, 2007
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Are we talking about stock brakes? You mention the pads are new.....how new? Are the rotors new or were they machined? If so, how long ago?

Does the pedal feel spongy or solid? How much travel in the pedal? Test the pedal feel under accel, decel, and idle...see if there is any difference.
 

stang8urimport

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  • Jul 19, 2007
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Well coming home today from work, I nailed the brakes coming off the interstate and it did the typically Fox body rear lock up. The front plowed and the rear came way up and the rear brakes locked up. Maybe it's just me used to my 07 which has 23982392 times better brakes. I never thought the brakes sucked so bad on my 90 till that thing lol
 

stang8urimport

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#8
  • Jul 19, 2007
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k, the pads are brand new Performance friction ceramics, the fronts and drilled and slotted brembos... The friction materials themselves are new front and rear. The problem is either hydraulic or possibly a booster problem.
 

Fett

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#9
  • Jul 19, 2007
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How new? How many miles on the new pads, how many miles on the rotors? Stock master, booster, and calipers?

How did you break them in?

It is possible that it is booster, but you need to examine the pedal feel under different circumstances, such as decel, accel, and idle. That will answer a lot of questions in regards to your booster and possible vac issues.

New pads tend to have a weak grab feel to them, the car just doesn't seem to stop as quickly as you would normally expect. Same with new or turned rotors.

I wouldn't be so quick to just focus on the booster or hydraulics. It is very possible that is where your problem lies, but it could be many other things as well.
 

Fett

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#10
  • Jul 19, 2007
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You also said rear pads....you have a 4 disk setup? What kind of master do you have? Go through the complete details on your entire brake system for us, so we can better help you.
 

stang8urimport

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  • Jul 20, 2007
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k, done asking questions. I understand this is the internet and stuff here, but I've already done the basics. I work on cars for a living. I've worked for Ford and many places inbetween. There is nothing basic about my problem here. It's hard asking questions on here because you guys always believe the person asking the questions are completely retarded. I need a little more advanced help. Guess I will look on Mitchels or Alldata. lol
 

ninety15.0

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#12
  • Jul 20, 2007
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well there big guy, in Fett's defense you did throw a pretty vague question up there. And you gave us no real helpful information on your braking system in the initial post. Just a "why do my brakes suck" question. Apparently you're one of those tech's....i guess you should just go check out AllData, its a great resource! lol
 

Fett

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#13
  • Jul 20, 2007
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PoopDawg said:
k, done asking questions. I understand this is the internet and stuff here, but I've already done the basics. I work on cars for a living. I've worked for Ford and many places inbetween. There is nothing basic about my problem here. It's hard asking questions on here because you guys always believe the person asking the questions are completely retarded. I need a little more advanced help. Guess I will look on Mitchels or Alldata. lol
Click to expand...


k, As someone who worked for a Ford dealership.....I am going to assume you have seen many ROs written with lines like "customer states sound coming from car while driving"....or "customer states steering doesn't feel right". What did you do when you got those tickets? You went right to the service adviser and blasted them for providing NO information. I see it every day.

You came on here hoping that someone had run into this same problem before, yet you didn't tell anybody exactly what your situation is. How would any of us have had the same experience when we don't even know what kind of brake system you have?

I was trying to help you because I too work for Ford, I built my car, and I recently had issues with my brakes....with the same exact symptoms as you decribe. But I don't want to give you information that might not pertain to your setup. If you have something completely different than I do, it might not be the same problem. So to assist you in the best way possible, we needed to know EXACTLY what you have installed.

When you want to drop the ego and attitude, please provide all possible information so we can help you. I am 100% sure someone on here will have the answer you need, but they can't help you if they don't know what kind of brakes you have.
 

stang8urimport

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#14
  • Jul 20, 2007
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It's ok. That's the reaction I was expecting from you guys. Thanks though.
 

ninety15.0

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#15
  • Jul 20, 2007
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What a tool....he sounds like he's all of about 15 years old.
 

stang8urimport

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#16
  • Jul 20, 2007
  • #16
I didn't come with personal attacks, you shouldn't either. I understand you guys are thinking one way, and it's not the right way so I said nevermind. You do know personal attacks can get you banned right?
 

Fett

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#17
  • Jul 20, 2007
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Who personally attacked you?? We are TRYING TO HELP YOU!!

The only "questionable" thing I said was that you needed to drop the attitude and ego and just provide us with the info requested. That isn't an attack, it is a statement, one I stick to. You had a major attitude when all I was trying to do was help you. You are acting like because you are a tech that asking questions on the internet is beneath you....as if we are nothing but internet children who couldn't possibly help such an awesome tech like yourself. That is how all your first posts came off....and I ignored that and tried to help you as well.

You have to remember, this forum has many people from all walks of life...including other techs, countermen (myself), and engineers, race car builders, ect. Just because we are posting on the internet doesn't mean we are video game nerds who know nothing about cars.

Obviously you are having trouble diagnosing a problem, we are here to help. Just like everybody else is here when I need help....and you know, so far my questions and help needed has resulted in 100% of my problems solved. The people who post here are top notch, nobody is here to poke fun of you because you are having a problem. Hell, even after the continued attitude, I want to put it all behind us and get back to helping solve your problem.

So please, I beg of you.....

Please give us the complete rundown of every brake component on your car, and describe in great detail exactly what your problem is. Also include what your thoughts are. Hopefully we can figure it out.
 

Mustang5L5

That is…until I whipped out my Bissell
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#18
  • Jul 20, 2007
  • #18
You still should be able to lock up the front driver's side wheel in any situation simply because this caliper receives direct pressure from the master cylinder and does not go through the prop valve at all. So even with a faulty prop valve, you should be able to lock it with a quick stab of the brakes.

What brand tires are you running? Are they very grippy?

Stock fox brakes are bad, but they shouldn't be that bad. How bad do the hoses look? You can maybe have someone stand on the brakes while you take a peek and see if they are ballooning out at all.
 

stang8urimport

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#19
  • Jul 20, 2007
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Mustang5L5 said:
You still should be able to lock up the front driver's side wheel in any situation simply because this caliper receives direct pressure from the master cylinder and does not go through the prop valve at all. So even with a faulty prop valve, you should be able to lock it with a quick stab of the brakes.

What brand tires are you running? Are they very grippy?

Stock fox brakes are bad, but they shouldn't be that bad. How bad do the hoses look? You can maybe have someone stand on the brakes while you take a peek and see if they are ballooning out at all.
Click to expand...

Thank you for the good responce. I'll just ignore those that type 4 paragraphs defending themselves.

I'm running BFG G-Force Sports on 93 Cobra replicas. 245/45/17 in the front, 275/40/17 in the rear. The hoses look visually ok with no cracks or anything. I think the idea of standing on the brakes while someone looks is great. I agree that it should def. lock up the LF tire seeing it's the most direct/shortest line. I've had boost problems on my old 83, and didn't have these same problems. The car also wears the original calipers and hoses, so I might just go ahead and replace them anyway with some new ones.
 

Mustang5L5

That is…until I whipped out my Bissell
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#20
  • Jul 20, 2007
  • #20
Well calipers and hoses are cheap enough you might want to replace them for the hell of it, but i don't think that's your prob. It could be, but i would think if a caliper was bad, one would be bad and you'd get a pull.

It could be a booster issue. A tiny leak could cause the brakes to be weak. Hard to say though.

There is only so much you can replace really.
 
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