The fuel gauge on my 2004 GMC Yukon did a strange thing yesterday. It pinned the fuel gauge showing way over full. At first I was thinking the sending unit has gone bad, but when the car is turned off the gauge only drops to half instead of all the way down. Because the gauge drops to half when the car is turned off and not all the way down I am beginning to think it may be a problem with the gauge cluster. There was a know issue and a Technical Service Bulliten for defective gauge clusters in 2004 GM trucks.
What do you think? Gauge cluster problem or sending unit going bad?