2004 Sierra Brake bleeding

[Bmac86]

I had to replace my brake lines on my 04 Sierra. I bled the brakes until only fluid was coming out. I then activated the abs vavle and re bled. Both rears and passenger front have no air coming out but the driver's side front still has air coming out. I've run about 3 quarts threw the system and spent about 3 hours. The pedal feels perfect when braking as well.

Any ideas on the cause?

[Brian715]

Three quarts??? Holy crap. Air must be being re-introduced somewhere.  master running dry? What process are you using for bleeding?  I have never used more than 1 quart unless replacing all the brake fluid. And even then never more than 2.