One problem related to back up lights has been reported for the 2015 GMC Yukon. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2015 GMC Yukon based on all problems reported for the 2015 Yukon.
All break lights stopped working at the same time on both sides of vehicle. Turn signal, back up lights, blinkers all still work. I was told the entire break light had to be replaced for a cost of apx 2k. It seems that this is a very common problem and the cost of repair is astronomical.