brakes failed

[albee9]

I have a 96 Silverado we were hauling a load and the brakes started to give .

so we pull over and i seen that the master cyl gasket was in bad shape I replaced it but still not a lot of pressure behind the peddle.

now I am thinking that they need to be bleed but I looked at different sources and I get confusing instructions.

I need to know how to do it the right way.

[MT-2500]

Originally Posted by albee9

I have a 96 Silverado we were hauling a load and the brakes started to give .

so we pull over and i seen that the master cyl gasket was in bad shape I replaced it but still not a lot of pressure behind the peddle.

now I am thinking that they need to be bleed but I looked at different sources and I get confusing instructions.

I need to know how to do it the right way.

What was in bad shape on master cylinder?
Like out of fluid or what?
4W Anti lock brakes?
When replacing master cylinder always bench bleed it first.
Then install and start bleeding at lines going out of master cylinder.
If anti lock and you did not get air in BPMV anti lock unit.
But it you opened the lines to antoi lock brake unit and let air in there you will need a brake bleeding capable scane to bleed anti lock unit.
After bench bleeding master cylinder and lines running out of it You can then finish bleeding brakes by pumping up pressure and opening up bleeder valves front and rear wheels.

Let us know how that goes.

[albee9]

No I do not think i need to replace the master cyl .

What I need to know is How to bleed the brakes the right way .

Some info I got says to bleed from RR towards the master ending at the LF (drivers side front) no need to bleed the abs part .

other info says bleed the abs unit first then the RR on to the LF and yet other info says to use a scanner to bleed the ABS then bleed the lines.

Whats the right way.

By the way It's a Kelsey-Hayes system.

[MT-2500]

Originally Posted by albee9

No I do not think i need to replace the master cyl .

What I need to know is How to bleed the brakes the right way .

Some info I got says to bleed from RR towards the master ending at the LF (drivers side front) no need to bleed the abs part .

other info says bleed the abs unit first then the RR on to the LF and yet other info says to use a scanner to bleed the ABS then bleed the lines.

Whats the right way.

By the way It's a Kelsey-Hayes system.

I explained about the ABS in upper post.

IF YOU DID NOT REPLACE MASTER CYLINDER WHY ARE YOU BLEEDING BRAKES?

[MT-2500]

To bleed regular brakes.
First install combination valve holder Kent moore J-39177 on combination valve.
Then bleed RR then LR then RF and then LF.

With the holding tool you may have to just bleed what ever wheels will bleed untill you get them all to bleed.

[albee9]

I am bleeding the brakes because I know that there is water and air in the lines.

Why else would the level go down when there is no leaks .

So I thought that it would be ok till I got the tools and info to do the job right but then when we tried to haul a load and the brakes started to fail .

that's why I need to bleed the brakes .

[Scrapper]

mt is rite on telling you the way to do this.

[MT-2500]

Originally Posted by albee9

I am bleeding the brakes because I know that there is water and air in the lines.

Why else would the level go down when there is no leaks .

So I thought that it would be ok till I got the tools and info to do the job right but then when we tried to haul a load and the brakes started to fail .

that's why I need to bleed the brakes .

How do you know that?
How far was it down?
Bad top gasket will lower fluid level.
Normal front pad wear will lower fluid level.
Master cylinder leakage or line leakage or caliper/wheel cylinder leaking will lower fluid level.

[albee9]

Originally Posted by MT-2500

How do you know that?
How far was it down?
Bad top gasket will lower fluid level.
Normal front pad wear will lower fluid level.
Master cylinder leakage or line leakage or caliper/wheel cylinder leaking will lower fluid level.

Well the level would be down at lease half every other day with everyday use

[MT-2500]

Originally Posted by albee9

Well the level would be down at lease half every other day with everyday use

You have a big problem there.
Bleeding is not going to help that.
Better hunt up the leak.
Post back where it is leaking.

[j cAT]

Originally Posted by albee9

I have a 96 Silverado we were hauling a load and the brakes started to give .

so we pull over and i seen that the master cyl gasket was in bad shape I replaced it but still not a lot of pressure behind the peddle.

now I am thinking that they need to be bleed but I looked at different sources and I get confusing instructions.

I need to know how to do it the right way.

pressure behind the brake pedal ? you mean hard pedal ? if so the brake booster or the vacuum line to it is defective....


If the brake fluid keeps dropping you must find the leak...

operating this vehicle with these conditions is dangerous to you and others on the road ...hauling weight with this is not too smart..

[albee9]

Originally Posted by j cAT

pressure behind the brake pedal ? you mean hard pedal ? if so the brake booster or the vacuum line to it is defective....


If the brake fluid keeps dropping you must find the leak...

operating this vehicle with these conditions is dangerous to you and others on the road ...hauling weight with this is not too smart..

I looked for leaking could not find any leaks and no I did not haul any thing with bad brakes.

We got very little braking only after we loaded the last load I have not and will not go on the road with bad brakes .

If you guys say there's a leak then I will look harder for it .

[j cAT]

Originally Posted by albee9

I looked for leaking could not find any leaks and no I did not haul any thing with bad brakes.

We got very little braking only after we loaded the last load I have not and will not go on the road with bad brakes .

If you guys say there's a leak then I will look harder for it .

if the fluid level drops you got a leak ............
removal of all tires inspect front calipers/hoses..


removal of rear wheels inspect the hoses/lines/brake cylinder...


inspect the brake lines from the master to the wheels...especially the line that runs next to the fuel tank / frame rail...

if your vehicle has other leaks this may be not easy to find..

using some paint thinner and a cloth clean up any leaks / stains in suspect areas then work the brake pedal to reveal leaks...

do you also have a hard brake pedal ????????

[albee9]

Originally Posted by j cAT

if the fluid level drops you got a leak ............
removal of all tires inspect front calipers/hoses..


removal of rear wheels inspect the hoses/lines/brake cylinder...


inspect the brake lines from the master to the wheels...especially the line that runs next to the fuel tank / frame rail...

if your vehicle has other leaks this may be not easy to find..

using some paint thinner and a cloth clean up any leaks / stains in suspect areas then work the brake pedal to reveal leaks...

do you also have a hard brake pedal ????????

Yes I will do all that and no I do not have a hard pedal it goes to the floor now

[Kevcules]

If your pedal goes to the floor,you have a leak somewhere.
Check the master cylinder reservoir,it's divided into two sections.
Is the front or back section low on fluid?
The larger section of fluid is for the front brakes and the smaller, the rear.
If you can't visually see any leaks,it must be behind your wheels.Pull them off and look.It's probably leaking at the rear brake cylinders.
Again , take the wheels off....

Kevin