Air in brakes tried everything!
hello everyone, I am fixing the brakes on a 2006 for a coworker. When he brought it to me the rear pads needed to be replaced and the fronts were down to the metal and ground into the rotors. I replaced all of the above but cannot get all of the air out of the brakes. I tried vacuum bleeding and it helped but i could still get the pedal to the floor. I put teflon tape on all of the bleeders and got a little more out. I tried my reverse bleeder and got the pedal to the firmest. I can still push the pedal about an inch with my hand with the car off. I tried the vacuum again and it didn't help i tried using the vacuum while pumping the pedal. I also wedged the brake pedal as far down as I could get it and let it sit overnight. I then vacuum bled all 4 and the pedal went to the floor again. Using a combination of vacuum bleeding and the reverse bleeder.
I don't know what else to try at this point. I've spent 10 hours on this and burned through 2 gallons of brake fluid.
only unusual thing is quiet hum for a second when i release the pedal. I've been using the cheap autozone dot 3, and i live at 6000ft if that makes any difference
thanks in advance