One problem related to alternator/generator/regulator has been reported for the 2008 GMC Yukon. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 GMC Yukon based on all problems reported for the 2008 Yukon.
My 2008 Yukon has had an electrical mystery for awhile now. When you open the doors the "chime" will be very faint and then the next time it's very loud. The clock resets like the battery has been disconnected after shutting the car off. The door locks will lock and unlock by themselves will I'm driving. I can turn the car off after driving it and it will be completely dead. It wont do anything. You can't lock the doors, turn on the radio, start the car or anything. Almost like it doesnt have a battery at all. Wait 10 minutes or so and slam a few doors and it starts right up. We've replaced batteries, alternators, fuses and taken it to mechanics with no luck. After replacing the battery it will work for several months and then it will do it again. There has to be a short somewhere and after googling it there are 1000 of people having the same problems. We had problems since we purchased the car in 2017 and I'm positive the owner before me had the same issues.