My Avalanche was always louder than I wanted when it came to the power steering, chalked it up as normal, well it seemed to get louder so I crawled under and sure enough the bottom side was wet w power steering fluid. Didn’t have time to wait for the replacement pump from online order so I just went to the local Chevy dealer to get OEM, $300 ouch. Also bought the $37 harbor freight pulley tool kit and went at it. Took a total of 8 hours taking my time and making a run to get a new o-ring. No real hiccups, cleaned up the underside that had caked on dirt,etc, filled w Lucas PS fluid and took it for a test drive. Big difference, it’s silent as a whisper now, due to the new pump, not the Lucas fluid