2007 Chevy suburban 2wd ls3 swapped, so heres what happened, wife driving home one night and the left front caliper was locking up(rotor had 50 degree difference from the others) so got it home took rotors and calipers off both sides when to oreilys to get new caliper, old one in hand so i did not have to pay a core charge. got home and have never been able to get a good pedal unless i pump it before stopping. i have replaced all 4 rotors, calipers, brake pads , master cylinder brake booster and abs module. i also have bleed the mess out of it, manually and with pressure and vacuum. i am at a lost as to what i should do, i really need some guidance! thanks guys and thanks for having me!