Wanted to add my experience, sorry if an old thread but Google brought me here... my problem was $1.19 o ring at the pump, on the pressure line.
https://youtu.be/POx8ug_gHa0
Seen here is the actual leak that srarted leaking and within 3 days fluid was dripping as seen in the video. Was quoted $500 like others for the new line... which I ordered and it came without the o-ring ? go figure.