Ok so i have changed the power steering pump 3 times in a 2006 trailblazer 4x4 ext with the 4.2. The pump acts like its deadheading and the last pump got so hot that the resivoir inlet actually melted shut. So i did some investigating and found several things and have talked to multiple mechanics. 1}bad rack....2}air in the system. 3}bad pump 4} need to bleed the system at the gear... so im completely lost now. Is there a bleeder on the steering box before it goes to the rack? Or no? This all started when the pressure line started to leak. Took it to a very dependable guy he replaced the bad line. Still no ps. Replaced the pump. Still nothing. Replaced the pump again. Still nothing. Today i replaced the pump and still no power steering. Can anyone help me or has anyone else had this same problem that can point me in the right direction?????? Please help!!