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Brakes on Tahoe


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Posted

I just found this site, and I hope I can get some input on my brake problem. I have a 1997 Tahoe 2 dr. 4x4 350 Auto. I have had the Tahoe for almost 2 years and cant figure out whats wrong with the brakes. It will not stop strong, it stops but will not by any means come to a screaming stop for lack of a better word. It is not a anti lock brake feel, it just wont stop good. I took it to a brake shop, all they said was thr rear brakes needed a slight adjustment, they did that for free, but it made no improvement at all. The pedal seems to have a lot of play in it. I have bled the brakes, I just am not sure if I did it right. How much fluid should be flushed out of each bleeder, I am thinking maybe I didnt flush enough out of the system? Or could It be something else wrong? The brake pads are fine, and the rotors are not groved at all. Thanks for any advice you can give.

Posted

Test for bubbles:

 

With the engine off, press the pedal a few times (like 10 or so) to discharge the booster.

 

Then, when pressing the pedal, it should easily drop about 1/4-1/2 inch...while the piston closes over the vent hole...then you're pressing on the fluid. After the vent hole closes, and without boost, the pedal should feel very hard. If there's any spongyness, without boost, you have air in there.

 

If you're not sure what it should feel like, try it on a newer vehicle, or one with no brake problems.

 

FWIW, I bleed our about 1 quart of fluid per wheel when bleeding. Overkill, but the fluid is relatively cheap.

Posted
I have had the Tahoe for almost 2 years and cant figure out whats wrong with the brakes.

 

Can't say for sure without actually driving it of course, but back in those model years, the brakes were not great. They all had a soft pedal with lots of travel and definitely did not throw you through the windshield when you slammed on the brakes.

 

You could probably spend a lot of time and money and you'll be right where you are when you started.

Posted
Test for bubbles:

 

With the engine off, press the pedal a few times (like 10 or so) to discharge the booster.

 

Then, when pressing the pedal, it should easily drop about 1/4-1/2 inch...while the piston closes over the vent hole...then you're pressing on the fluid.  After the vent hole closes, and without boost, the pedal should feel very hard.  If there's any spongyness, without boost, you have air in there.

 

If you're not sure what it should feel like, try it on a newer vehicle, or one with no brake problems.

 

FWIW, I bleed our about 1 quart of fluid per wheel when bleeding.  Overkill, but the fluid is relatively cheap.

 

 

 

I have been just letting a couple of squirts come out of each bleeder, I have not seen any bubbles doing this. Am I not letting enough fluid go thru the lines? If you are saying a quart, I guess I better try again, and use lots more fluid.
Posted

What are the symptoms of a bad Master Cylinder? Maybe I am off course on the bleeding the lines, and the Master Cylinder is bad? The thing that makes me think that is needs bled is that for almost 2 years, it has been the same, no worse, no better?

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