I have replaced most the front brake lines and the master cylinder, the back brakes are working the front aren't, I have been working on this for two weeks , any help would be appreciated , Thanks . By the way this is a 2002 Silverado 1500

 

does the brake pedal feel spongy or go deep to the floor? does it firm up when pumping the pedal?

 

Doesn't firm up, I can bleed the back breaks fine, but not the front, they never go to the floor ,

 

so you're not getting fluid out of the front when you try to bleed? Did you bench bleed the master cylinder? I would try opening a front bleeder and see if it will gravity bleed or if you can put vacuum on it to get fluid flowing.

 

Bleeding not complete.
Clevelands suggestions are solid.

 

Been there , done that, Front caliber moving slightly, It just won't pump up

 

there should be a porporation valve on the frame and it might be bad !