Booster is not ruled out, and neither is the EBCM at this point. Just trying to diagnose without throwing a ton of money at it needlessly.

Check those braided lines from the master to the proportiong valve. Make sure there are no kinks.

 

Well, I'm gonna try one more time:
unless this has been checked, the booster can not be eliminated. Print the {larger}image, here
and ask your mechanic if he checked this.

 

Thanks guys, I will get that checked. I am such a rookie.

 

Here is an update. The steel braided lines appear to be normal, no kinks. Taking it to a GM tech friend of a friend Saturday. I will have a copy of the image you posted Pettyfog and make sure he checks it. I had to stop driving the truck yesterday. I was able to get to work in the mornings with little binding. But going home the last couple of afternoons the binding occurs much sooner and last afternoon it became more severe.I don't want to burn up my new brakes. I just want a straight answer, when the fuse is pulled from the ABS, does that disable the ABS system, when disabled will it have no effect on the brake system, the only effect would be the ABS system would not operate.. The local chevrolet dealer told me that when I had the truck diagnosed. But from what I have read here that may not be true. Where do you purchase the EBCM and the BPMV and how much will the parts cost? Thanks for your help and information.

 

I replaced both ebcm and bpmv and solved my problems.....new they cost something like$500-$600 i got one from the u pull it for $108 from a blazer with 45000 miles on it

 

Thanks Mad, I will keep looking for used parts.

 

Okay, I have resolved my brake issue. I replaced the master cylinder and all is well now. I still have the Brake light and ABS light coming on most of the time, but no more brake dragging. Any suggestions on replacing the EBCM and BPMV, new or used? where to locate either? all suggestions appreciated. Thanks.

 

It would be nice to know WHAT was wrong with the master cylinder, but oh, well.
REALLY people, this SHOULD be a 2 way street!

I think reading back through the thread the ABS option is obvious. From what I've seen on here there's not a chronic critical fault in the ABS, the failure is the typical random 'anythinng can happen' paradigm.

And on most cars the 'brake warning light' is triggered by any of three things:
- MC fluid level
- Proportioning Valve displacement
and QUITE OFTEN..
- parking brake 'on' warning switch. You should be able to find any prob with this by yourself. It's right there at your feet.

{heh.. I HATE when I see 'break' typed for brake but I just did it myself}