Bleeding Brakes on a 2001 Silverado Z71

To my knowledge, the porportioning valve can't be bled using the ABS bleed feature of a scan tool and has to be manually bled.

The brakes will need to be bled normally, and GM has a depressor tool specifically made to be installed on the valve while bleeding the brakes: J-39177.

You'll have to bleed the front and rear brakes as normal, but with the tool installed in order to remove the air trapped in the valve.

Lots of video help in the link. Some vehicles have a shim kit which you have to buy as an extra part kit. Mine does.

https://www.google.com/search?q=2001+Chevy+Silverado+brake+caliper+not+releasing

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at this point I suspect that it is as it appears not to be bleed the second 1/2 of the cylinder
You can get a book and follow the bleeding procedure as some GM product master cylinders require a switch,pin to be removed and a plug put in so that the pistons can move to allow the bleeding process
you could take it to a brake shop and ask what has to be done to get the master cylinder to bleed properly
getting a workshop manual would be a good place to start as bleeding brakes is not always simple unless you know how it all works

I do believe you have to put your truck on a scanner to bleed the brakes properly. I have done it a few times to get the pedal back up. After some one else has worked on them. Usually it's because the ABS pump was run dry. But check for fluid around the brake booster, it will be wet and eating the paint off it. Replace the master cylinder first. Bleed, and if you still have the problem. Get it on a scanner.

last time I replaced a wheel cylinder on one of those I had to pressure bleed the air out 12 times ( a record i must say) and no my normal method of vac bleeding fluid did not work at all , Im guessing it's got to do with gm's abs "motor" this all arrumes that son did not dammage wheel speed sensor too
a code ck will tell all

Ok many people have this problem when they do brakes that ABS equiped. First of all make sure that all your connection are tight at the calipers. Check and make sure you have no visible leaks at all every where on the vehicle. Second alot of people do not know that the vehicle must be running when you bleed the brakes when the vehicle has ABS brakes. So the solution to your problem is very simple check to make sure master cylinder is full, then start your vehicle and have some one pump the brakes then hold down and open bleeder valve. You need to do this several times with ABS brakes,make sure you continue to check master cylinder fluid level continuously. Always start bleeding the brake that is farthest away from master cylinder first then continue to work your way to the closesest. Remeber when bleeding brakes when equiped with ABS the vehicle must be running to allow the ABS pump to run and bleed as well.

sounds like only one side of your master cylinder is working, replace the master cylinder.

When you bleed your brakes you have to start at the wheel longest distance from the master cylinder keep bleeding and putting fresh fluid in until fresh fluid comes out the bleeder screw do this by pumping brakes real slow tighten screw. do this at each wheel working your way closer to the master cylinder. The point of doing this is to replace old fluid and if done right you get all the air out of the brake system. You still have air in the system have you tried to put the lid back on your brake fluid reservoir and pump your brakes to the floor they should get tight unless you have a lot of air in the system. you mave have to do each wheel again just to get the air out.

What was the purpose of bleeding, what did you replace?

crawl underneath the front and look at the caliper if it has a duel piston caliper you will see 2 circles about 3 inches across and if it is a single piston caliper it will only have one of these circles in the middle this iswhere the pistons are. yes those pads are suitable. As for bleeding the brakes you need to start at the passengers side rear wheel and bleed it first then go to the drivers side rear wheel then go to the passengers side front wheel and then finally the drivers side front wheel. If you are only replacing the brake pads and shoes then you don't need to bleed the brakes. If you are bleeding the brakes then you will want to be sure to top up the brake fluid as you are doing thebleeding process as if you don't you will end up having to start all over again. as for special tools you may need a 3/8 hex bit and a 8 inch " C " clamp to compress the calipers after you remove the brake pads. If you are replacing the rotors you may require a special socket fo dis-assebleing and re-assembly of the front hubs.