GM Drivetrain & Suspension Chassis | Transmission| Driveshaft | Gears/Rear End/Differential | Traction Aids

Aaaaaaahhhhhhhhhh!!!!!!!!!!!!!!

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Old 04-19-2011 | 04:56 PM
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Default Aaaaaaahhhhhhhhhh!!!!!!!!!!!!!!

I ******* HATE THE BRAKES ON THESE GODDDAMN TRUCKS!!!!!!!!


I just replaced the rear rotors and pads. Stock rotors and Carquest Gold pads (those pads are absolutely amazing, from past experiences). I have such a ridiculously soft pedal its disgusting. There is no air in the lines, NONE. I have bled this thing so many times, the fluid has been completely cycled, probably twice. Also had the ABS unit pulsed while power bleeding! I can still push the pedal to the floor without the ABS activating!!! The master is only about 20K old, WTF? I am pulling 17" of vacuum at idle, so that shouldn't be the issue.


Rant over, now for the questions...

1. I would say that I want to put the brakes off a C5 vette on there, but that won't solve the problem.

2. I have narrowed it down to either the vacuum power assist OR the ABS unit itself

3. Does anyone know how to test the power assist?

4. Aside from obviously loosing the ABS function, is there any other down sides to ripping out the ABS unit altogether and can the code be deleted?


This truck is not safe to drive like this. It stops, but it takes FOREVER. And, when I press the pedal, I can feel the initial squeeze, then it almost feels like it releases (looses pressure for a split second), then it starts to bite down again, by this time, my foot is almost at the damn floor.


Please someone chime in with something, I am loosing my bloody mind
Old 04-19-2011 | 04:59 PM
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went back and deleted all the "*****". it was hard to read.
Old 04-19-2011 | 04:59 PM
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i feel the same way. once i get my truck back up and running im guna try out some braided lines. i hear you can feel a difference with them.
Old 04-19-2011 | 05:08 PM
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Same here, swapped to powerslot rotors in the front, no difference. Got the hydroboost stuff I picked up at a local junkyard sitting in my garage, I am hoping that fixes it.
Old 04-19-2011 | 05:09 PM
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Originally Posted by TXsilverado
i feel the same way. once i get my truck back up and running im guna try out some braided lines. i hear you can feel a difference with them.
I have talked to a few people who did the braided lines, and they said it helps with pedal feel (more positive, less mushy), but doesn't improve actual braking performance.
Old 04-19-2011 | 05:23 PM
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I have to imagine the Hydroboost conversion will fix it. But, i would set the truck on fire if the problem persisted. I am going to see if I can find on any info on the power assist to try to test it. if anyone has the factory service manual (the real one, not the Hayne's / Chilton's garbage) that would check for me, that'd be awesome.
Old 04-19-2011 | 05:54 PM
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Found this stuff. I think that they are the GM Tech training curriculum. Doesn't really help me, but good info anyway.

http://student.ccbcmd.edu/~smacadof/..._m01_Final.pdf

http://student.ccbcmd.edu/~smacadof/..._m02_Final.pdf

http://student.ccbcmd.edu/~smacadof/..._m03_Final.pdf

http://student.ccbcmd.edu/~smacadof/..._m04_Final.pdf

http://student.ccbcmd.edu/~smacadof/..._m05_Final.pdf

http://student.ccbcmd.edu/~smacadof/..._m06_Final.pdf

http://student.ccbcmd.edu/~smacadof/..._m07_Final.pdf

http://student.ccbcmd.edu/~smacadof/..._m08_Final.pdf
Old 04-19-2011 | 06:34 PM
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Subscribed for summaries of the above manuals...

EDIT: Actually, those things are pretty useful, nice find!

Last edited by TX Tahoe Z71; 04-19-2011 at 06:49 PM.
Old 04-19-2011 | 09:41 PM
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Originally Posted by 03 BLACKOUTSSS
I have to imagine the Hydroboost conversion will fix it. But, i would set the truck on fire if the problem persisted. I am going to see if I can find on any info on the power assist to try to test it. if anyone has the factory service manual (the real one, not the Hayne's / Chilton's garbage) that would check for me, that'd be awesome.
If your pedal is going to the floor, the hydroboost stuff isn't going to fix it. Brakes are a hydraulic system. Fluid doesn't compress. So if you have excessive pedal travel, you need to figure out what it is.

First thing to try, put the vehicle in drive and hold the brake pedal. Do this with some room around you. Does the vehicle eventually start to move with the pedal held? If so, if it's not an external leak, it's your master cylinder.

Have someone pump the brakes while you checked to see if the lines are expanding. After a while, the rubber lines will wear out and expand keeping the pressure from making it to the caliper.

If the lines are good, it could be air in the system. They can be a bitch to bleed sometimes.

As for the manuals, I just looked at the first one but if they are all the same source then they are the ASEP manuals. They are what GM uses to train future techs.
Old 04-19-2011 | 09:47 PM
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mines feel like crap... i got drums in the rear..



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