Bleeding the brakes

[yellowkid]

I had the steel front brake line go as seems to be common with these, and just wrapping up the replacement. I used the GM pre-bent kit and it turned out to be time consuming but not too hard. now here's the question -- is bleeding just like normal? I've heard ABS complicates things. I did replace all four front lines and the two front flexible lines. did not touch the master cylinder, but it surely emptied when the line broke. the four lines went it to what I assume is the ABS block about half-way back. Any hints would be appreciated! TIA john p

 

[Silent D]

I replaced all 4 brakes and bled them as normal and can't get them to feel like normal. I've bleed them multiple times and still nothing (have to double pump to get a normal felling pedal) so I'm going to have the dealer bleed it. From what I've looked up they hook a laptop up to the Tahoe and bleed the ABS module. Then I won't have to worry about it while towing my boat. $150 is well worth peace of mind.

 

[M1Gunner]

@yellowkid You will need to perform an ABS bleed via scan tool. Does not have to be a dealer, any higher end scan tool has the capabilities.

@Silent D depending on how much fluid was lost when the work was done will determine how far you need to take it. If you’ve had the ABS system bled and it still feels that soft then you still have air in the lines. You may need to bleed the entire system, including the master cylinder. Then again you may just have a bad master cylinder leaking internally.

 

[Silent D]

@yellowkid You will need to perform an ABS bleed via scan tool. Does not have to be a dealer, any higher end scan tool has the capabilities.

@Silent D depending on how much fluid was lost when the work was done will determine how far you need to take it. If you’ve had the ABS system bled and it still feels that soft then you still have air in the lines. You may need to bleed the entire system, including the master cylinder. Then again you may just have a bad master cylinder leaking internally.

The brakes felt fine before I replaced the pads so I assume it's air in the lines. I don't have a scam tool so I can't bleed the ABS Module my self.

 

[M1Gunner]

why did you have to open the system if you only changed the pads though?

 

[brasil]

the problem is the abs block..... try the following. raise the rear of the car bleed the four calipers.
...then turn on the ignition... turn one wheel, while a fried bleeds the right rear wheel caliper.
the trick is that the abs block traps air. and while you are turning the wheel, the abs block thinks that he has to regulate . so one of the valves opens and let the fluid pass trough. if you do this on all4 wheels - normally the air shoud disappear

 

[RED TAHOE LS]

Quote from Silent D

bleed the ABS module. Then I won't have to worry about it while towing my boat. $150 is well worth peace of mind.

If your not sure or do not have the equipment, leave it to the pro's. JMHO and good luck.
David g..........

 

[Silent D]

the problem is the abs block..... try the following. raise the rear of the car bleed the four calipers.
...then turn on the ignition... turn one wheel, while a fried bleeds the right rear wheel caliper.
the trick is that the abs block traps air. and while you are turning the wheel, the abs block thinks that he has to regulate . so one of the valves opens and let the fluid pass trough. if you do this on all4 wheels - normally the air shoud disappear

This is the issue at hand. Thanks for the info.

If your not sure or do not have the equipment, leave it to the pro's. JMHO and good luck.
David g..........

I could do it, just over it at this point lol. I have free lifetime oil changes at the dealership I bought from so next time it goes in for that I'll just have them flush the brake system and be done with it.

 

[Silent D]

why did you have to open the system if you only changed the pads though?

I had to replace all the bleed valves cause they were rusted, seized and rounded off. So I was pretty pissed, then had my wife pumping and holding the bark pedal, which caused more frustration. I ended up letting the master cylinder get air in it. Completely my fault.