Hi all, new here but not to the service repairs (over 40 years). Anyway I would like to share something I run in to with my 05 4.8 Yucon. it would just shut down randomly. Sure you all know about the grounding issues. Well my problem was at the ground below cylinder 3, and not the connection at the bolt and eye let but where the wire crimped around the wire. replaced it with a heat shrink eye let and used heat shrink to 2" after the connection. That ground powers the ignition coil I believe.